Document and Entity Information	3 Months Ended
Document and Entity Information	Mar. 31, 2015	Apr. 30, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	ED
Entity Registrant Name	CONSOLIDATED EDISON INC
Entity Central Index Key	0001047862
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		292,877,149
CECONY [Member]
Document Information [Line Items]
Entity Registrant Name	CONSOLIDATED EDISON CO OF NEW YORK INC
Entity Central Index Key	0000023632
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer

Consolidated Income Statement (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
OPERATING REVENUES
Electric	$ 2,135	$ 2,237
Gas	732	882
Steam	375	341
Non-utility	374	329
TOTAL OPERATING REVENUES	3,616	3,789
OPERATING EXPENSES
Purchased power	884	963
Fuel	154	156
Gas purchased for resale	262	400
Other operations and maintenance	814	825
Depreciation and amortization	279	261
Taxes, other than income taxes	497	499
TOTAL OPERATING EXPENSES	2,890	3,104
OPERATING INCOME	726	685
OTHER INCOME (DEDUCTIONS)
Investment and other income	5	12
Allowance for equity funds used during construction	1	1
Other deductions	(2)	(3)
TOTAL OTHER INCOME	4	10
INCOME BEFORE INTEREST AND INCOME TAX EXPENSE	730	695
INTEREST EXPENSE
Interest on long-term debt	156	146
Other interest	6	(9)
Allowance for borrowed funds used during construction	(1)	(1)
NET INTEREST EXPENSE	161	136
INCOME BEFORE INCOME TAX EXPENSE	569	559
INCOME TAX EXPENSE	199	198
NET INCOME FOR COMMON STOCK	370	361
Net income for common stock per common share-basic	$ 1.26	$ 1.23
Net income for common stock per common share-diluted	$ 1.26	$ 1.23
DIVIDENDS DECLARED PER SHARE OF COMMON STOCK	$ 0.65	$ 0.63
AVERAGE NUMBER OF SHARES OUTSTANDING-BASIC (IN MILLIONS)	292.9	292.9
AVERAGE NUMBER OF SHARES OUTSTANDING-DILUTED (IN MILLIONS)	293.9	294.1
CECONY [Member]
OPERATING REVENUES
Electric	1,980	2,074
Gas	655	789
Steam	375	341
TOTAL OPERATING REVENUES	3,010	3,204
OPERATING EXPENSES
Purchased power	539	617
Fuel	154	156
Gas purchased for resale	198	346
Other operations and maintenance	703	725
Depreciation and amortization	257	240
Taxes, other than income taxes	475	477
TOTAL OPERATING EXPENSES	2,326	2,561
OPERATING INCOME	684	643
OTHER INCOME (DEDUCTIONS)
Investment and other income	2	7
Allowance for equity funds used during construction	1	1
Other deductions	(2)	(2)
TOTAL OTHER INCOME	1	6
INCOME BEFORE INTEREST AND INCOME TAX EXPENSE	685	649
INTEREST EXPENSE
Interest on long-term debt	141	128
Other interest	4	3
Allowance for borrowed funds used during construction
NET INTEREST EXPENSE	145	131
INCOME BEFORE INCOME TAX EXPENSE	540	518
INCOME TAX EXPENSE	192	184
NET INCOME FOR COMMON STOCK	$ 348	$ 334

Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
NET INCOME	$ 370	$ 361
OTHER COMPREHENSIVE INCOME, NET OF TAXES
Pension and other postretirement benefit plan liability adjustments, net of taxes	5	4
TOTAL OTHER COMPREHENSIVE INCOME, NET OF TAXES	5	4
COMPREHENSIVE INCOME FOR COMMON STOCK	375	365
CECONY [Member]
NET INCOME	348	334
OTHER COMPREHENSIVE INCOME, NET OF TAXES
Pension and other postretirement benefit plan liability adjustments, net of taxes		1
TOTAL OTHER COMPREHENSIVE INCOME, NET OF TAXES		1
COMPREHENSIVE INCOME	$ 348	$ 335

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References+ Details

Consolidated Statement of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES
NET INCOME	$ 370	$ 361
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	279	261
Deferred income taxes	178	195
Rate case amortization and accruals	(14)	32
Common equity component of allowance for funds used during construction	(1)	(1)
Net derivative gains	(8)	(20)
Other non-cash items (net)	5	4
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers, less allowance for uncollectibles	(243)	(315)
Special deposits	2	324
Materials and supplies, including fuel oil and gas in storage	40	60
Other receivables and other current assets	(5)	8
Income taxes receivable	224
Prepayments	(307)	(353)
Accounts payable	(58)	113
Pensions and retiree benefits obligations (net)	185	193
Pensions and retiree benefits contributions	(204)	(200)
Accrued taxes	8	(378)
Accrued interest	48	(39)
Superfund and environmental remediation costs (net)	8	9
Distributions from equity investments related to renewable electric production projects	17
Deferred charges, noncurrent assets and other regulatory assets	35	(76)
Deferred credits and other regulatory liabilities	33	86
Other current and noncurrent liabilities	(33)	(40)
NET CASH FLOWS FROM OPERATING ACTIVITIES	559	224
INVESTING ACTIVITIES
Utility construction expenditures	(550)	(498)
Cost of removal less salvage	(50)	(47)
Non-utility construction expenditures	(42)	(61)
Investments in renewable electric production projects	(35)	(80)
Proceeds from grants related to solar electric production projects		36
Return of equity investments related to renewable electric production projects	6
Restricted cash	4	16
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(667)	(634)
FINANCING ACTIVITIES
Net payment of short-term debt	(281)	(621)
Issuance of long-term debt		850
Retirement of long-term debt		(200)
Debt issuance costs	(1)	(6)
Common stock dividends	(190)	(184)
Issuance of common shares for stock plans, net of repurchases	(2)	(1)
NET CASH FLOWS USED IN FINANCING ACTIVITIES	(474)	(162)
CASH AND TEMPORARY CASH INVESTMENTS:
NET CHANGE FOR THE PERIOD	(582)	(572)
BALANCE AT BEGINNING OF PERIOD	699	674
BALANCE AT END OF PERIOD	117	102
Cash paid/(received) during the period for:
Interest	105	91
Income taxes	(197)	416
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	190	151
CECONY [Member]
OPERATING ACTIVITIES
NET INCOME	348	334
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	257	240
Deferred income taxes	127	178
Rate case amortization and accruals	(14)	32
Common equity component of allowance for funds used during construction	(1)	(1)
Other non-cash items (net)	1	2
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers, less allowance for uncollectibles	(196)	(265)
Materials and supplies, including fuel oil and gas in storage	40	46
Other receivables and other current assets	57	122
Accounts receivable from affiliated companies	108	(171)
Prepayments	(278)	(295)
Accounts payable	(48)	12
Pensions and retiree benefits obligations (net)	178	184
Pensions and retiree benefits contributions	(203)	(200)
Accrued taxes		(11)
Accrued interest	39	40
Superfund and environmental remediation costs (net)	7	9
Accrued taxes to affiliated companies	25	(203)
Deferred charges, noncurrent assets and other regulatory assets	28	(115)
Deferred credits and other regulatory liabilities	43	105
Other current and noncurrent liabilities	(38)	(32)
NET CASH FLOWS FROM OPERATING ACTIVITIES	480	11
INVESTING ACTIVITIES
Utility construction expenditures	(519)	(464)
Cost of removal less salvage	(49)	(46)
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(568)	(510)
FINANCING ACTIVITIES
Net payment of short-term debt	(182)	(541)
Issuance of long-term debt		850
Retirement of long-term debt		(200)
Debt issuance costs	(1)	(6)
Dividend to parent	(338)	(178)
NET CASH FLOWS USED IN FINANCING ACTIVITIES	(521)	(75)
CASH AND TEMPORARY CASH INVESTMENTS:
NET CHANGE FOR THE PERIOD	(609)	(574)
BALANCE AT BEGINNING OF PERIOD	645	633
BALANCE AT END OF PERIOD	36	59
Cash paid/(received) during the period for:
Interest	99	85
Income taxes	(86)	276
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	$ 138	$ 120

Consolidated Balance Sheet (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS
Cash and temporary cash investments	$ 117	$ 699
Special deposits	6	8
Accounts receivable - customers, less allowance for uncollectible accounts	1,444	1,201
Other receivables, less allowance for uncollectible accounts	149	133
Income taxes receivable		224
Accrued unbilled revenue	456	500
Fuel oil, gas in storage, materials and supplies, at average cost	332	372
Prepayments	470	163
Regulatory assets	66	148
Deferred tax assets	95	128
Other current assets	263	278
TOTAL CURRENT ASSETS	3,398	3,854
INVESTMENTS	814	816
UTILITY PLANT AT ORIGINAL COST
General	2,479	2,465
TOTAL	36,378	35,909
Less: Accumulated depreciation	7,702	7,614
Net	28,676	28,295
Construction work in progress	947	1,031
NET UTILITY PLANT	29,623	29,326
NON-UTILITY PLANT
Non-utility property, less accumulated depreciation	402	388
Construction work in progress	187	113
NET PLANT	30,212	29,827
OTHER NONCURRENT ASSETS
Goodwill	429	429
Intangible assets, less accumulated amortization of $4 in 2015 and 2014	3	3
Regulatory assets	8,906	9,156
Other deferred charges and noncurrent assets	215	223
TOTAL OTHER NONCURRENT ASSETS	9,553	9,811
TOTAL ASSETS	43,977	44,308
CURRENT LIABILITIES
Long-term debt due within one year	496	560
Notes payable	519	800
Accounts payable	937	1,019
Customer deposits	345	344
Accrued taxes	80	72
Accrued interest	180	132
Accrued wages	100	95
Fair value of derivative liabilities	37	64
Regulatory liabilities	240	187
Other current liabilities	473	508
TOTAL CURRENT LIABILITIES	3,407	3,781
NONCURRENT LIABILITIES
Provision for injuries and damages	185	182
Pensions and retiree benefits	3,629	3,914
Superfund and other environmental costs	758	764
Asset retirement obligations	191	188
Fair value of derivative liabilities	24	13
Deferred income taxes and investment tax credits	9,257	9,076
Regulatory liabilities	1,892	1,993
Other deferred credits and noncurrent liabilities	170	181
TOTAL NONCURRENT LIABILITIES	16,106	16,311
LONG-TERM DEBT	11,694	11,631
EQUITY
Common shareholders' equity	12,761	12,576
Noncontrolling interest	9	9
TOTAL EQUITY (See Statement of Equity)	12,770	12,585
TOTAL LIABILITIES AND EQUITY	43,977	44,308
CECONY [Member]
CURRENT ASSETS
Cash and temporary cash investments	36	645
Special deposits	2	2
Accounts receivable - customers, less allowance for uncollectible accounts	1,260	1,064
Other receivables, less allowance for uncollectible accounts	60	71
Accrued unbilled revenue	326	384
Accounts receivable from affiliated companies	24	132
Fuel oil, gas in storage, materials and supplies, at average cost	272	312
Prepayments	404	126
Regulatory assets	51	132
Deferred tax assets	45	94
Other current assets	122	158
TOTAL CURRENT ASSETS	2,602	3,120
INVESTMENTS	278	271
UTILITY PLANT AT ORIGINAL COST
General	2,275	2,265
TOTAL	34,025	33,584
Less: Accumulated depreciation	7,048	6,970
Net	26,977	26,614
Construction work in progress	893	971
NET UTILITY PLANT	27,870	27,585
NON-UTILITY PLANT
Non-utility property, less accumulated depreciation	5	5
NET PLANT	27,875	27,590
OTHER NONCURRENT ASSETS
Regulatory assets	8,251	8,481
Other deferred charges and noncurrent assets	174	175
TOTAL OTHER NONCURRENT ASSETS	8,425	8,656
TOTAL ASSETS	39,180	39,637
CURRENT LIABILITIES
Long-term debt due within one year	350	350
Notes payable	268	450
Accounts payable	709	802
Accounts payable to affiliated companies	24	23
Customer deposits	331	330
Accrued taxes	46	46
Accrued taxes to affiliated companies	35	10
Accrued interest	156	117
Accrued wages	92	84
Fair value of derivative liabilities	23	48
Regulatory liabilities	212	142
Other current liabilities	377	415
TOTAL CURRENT LIABILITIES	2,623	2,817
NONCURRENT LIABILITIES
Provision for injuries and damages	178	176
Pensions and retiree benefits	3,222	3,493
Superfund and other environmental costs	662	666
Asset retirement obligations	187	185
Fair value of derivative liabilities	16	10
Deferred income taxes and investment tax credits	8,367	8,257
Regulatory liabilities	1,728	1,837
Other deferred credits and noncurrent liabilities	135	144
TOTAL NONCURRENT LIABILITIES	14,495	14,768
LONG-TERM DEBT	10,864	10,864
EQUITY
Common shareholders' equity	11,198	11,188
TOTAL LIABILITIES AND EQUITY	39,180	39,637
Electric [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	25,410	25,091
Electric [Member] \| CECONY [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	23,902	23,599
Gas [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	6,223	6,102
Gas [Member] \| CECONY [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	5,582	5,469
Steam [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	2,266	2,251
Steam [Member] \| CECONY [Member]
UTILITY PLANT AT ORIGINAL COST
Utility plant, at original cost	$ 2,266	$ 2,251

Consolidated Balance Sheet (Parenthetical) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounts receivable - customers, allowance for uncollectible accounts	$ 96	$ 96
Other receivables, allowance for uncollectible accounts	11	10
Non-utility property, accumulated depreciation	95	91
Intangible assets, accumulated amortization	4	4
CECONY [Member]
Accounts receivable - customers, allowance for uncollectible accounts	90	90
Other receivables, allowance for uncollectible accounts	9	8
Non-utility property, accumulated depreciation	$ 25	$ 25

Consolidated Statement of Shareholder's Equity (USD $) In Millions, except Share data	Total	CECONY [Member]	Common Stock [Member]	Common Stock [Member] CECONY [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] CECONY [Member]	Retained Earnings [Member]	Retained Earnings [Member] CECONY [Member]	Treasury Stock [Member]	Capital Stock Expense [Member]	Capital Stock Expense [Member] CECONY [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]	Accumulated Other Comprehensive Income/(Loss) [Member] CECONY [Member]	Noncontrolling Interest [Member]	Repurchased Con Edison Stock [Member] CECONY [Member]
BALANCE at Dec. 31, 2013		$ 10,847		$ 589		$ 4,234		$ 7,053			$ (61)		$ (6)		$ (962)
BALANCE at Dec. 31, 2013	12,245		32		4,995		8,338		(1,034)	(61)		(25)
BALANCE (in shares) at Dec. 31, 2013			292,872,396	235,488,094					23,210,200
Net income for common stock	361	334					361
NET INCOME	361	334						334
Common stock dividends	(184)	(178)					(184)	(178)
Issuance of common shares for stock plans, net of repurchases					(2)				2
Issuance of common shares for stock plans, net of repurchases (in shares)			51,656						(51,656)
Other comprehensive income	4	1										4	1
BALANCE at Mar. 31, 2014	12,426		32		4,993		8,515		(1,032)	(61)		(21)
BALANCE at Mar. 31, 2014		11,004		589		4,234		7,209			(61)		(5)		(962)
BALANCE (in shares) at Mar. 31, 2014			292,924,052	235,488,094					23,158,544
BALANCE at Dec. 31, 2014	12,576	11,188		589		4,234		7,399			(61)		(11)		(962)
BALANCE at Dec. 31, 2014	12,585		32		4,991		8,691		(1,032)	(61)		(45)		9
BALANCE (in shares) at Dec. 31, 2014			292,876,196	235,488,094					23,206,400
Net income for common stock	370	348					370
NET INCOME	370	348						348
Common stock dividends	(190)	(338)					(190)	(338)
Issuance of common shares for stock plans, net of repurchases					2				(2)
Issuance of common shares for stock plans, net of repurchases (in shares)			24,600						(24,600)
Other comprehensive income	5											5
Noncontrolling interest	9
BALANCE at Mar. 31, 2015	12,770		32		4,993		8,871		(1,034)	(61)		(40)		9
BALANCE at Mar. 31, 2015	$ 12,761	$ 11,198		$ 589		$ 4,234		$ 7,409			$ (61)		$ (11)		$ (962)
BALANCE (in shares) at Mar. 31, 2015			292,900,796	235,488,094					23,181,800

General	3 Months Ended
General	Mar. 31, 2015
General	General These combined notes accompany and form an integral part of the separate consolidated financial statements of each of the two separate registrants: Consolidated Edison, Inc. and its subsidiaries (Con Edison) and Consolidated Edison Company of New York, Inc. and its subsidiaries (CECONY). CECONY is a subsidiary of Con Edison and as such its financial condition and results of operations and cash flows, which are presented separately in the CECONY consolidated financial statements, are also consolidated, along with those of Con Edison’s other utility subsidiary, Orange and Rockland Utilities, Inc. (O&R) and Con Edison’s competitive energy businesses (discussed below) in Con Edison’s consolidated financial statements. The term “Utilities” is used in these notes to refer to CECONY and O&R. As used in these notes, the term “Companies” refers to Con Edison and CECONY and, except as otherwise noted, the information in these combined notes relates to each of the Companies. However, CECONY makes no representation as to information relating to Con Edison or the subsidiaries of Con Edison other than itself. The separate interim consolidated financial statements of each of the Companies are unaudited but, in the opinion of their respective managements, reflect all adjustments (which include only normally recurring adjustments) necessary for a fair presentation of the results for the interim periods presented. The Companies’ separate interim consolidated financial statements should be read together with their separate audited financial statements (including the combined notes thereto) included in Item 8 of their combined Annual Report on Form 10-K for the year ended December 31, 2014. Con Edison has two regulated utility subsidiaries: CECONY and O&R. CECONY provides electric service and gas service in New York City and Westchester County. The company also provides steam service in parts of Manhattan. O&R, along with its regulated utility subsidiaries, provides electric service in southeastern New York and adjacent areas of northern New Jersey and eastern Pennsylvania and gas service in southeastern New York and adjacent areas of eastern Pennsylvania. Con Edison has the following competitive energy businesses: Consolidated Edison Solutions, Inc. (Con Edison Solutions), a company which sells to retail customers electricity purchased in wholesale markets, enters into related hedging transactions and also provides energy-related products and services to retail customers; Consolidated Edison Energy, Inc. (Con Edison Energy), a company that provides energy-related products and services to wholesale customers; and Consolidated Edison Development, Inc. (Con Edison Development), a company that develops, owns and operates renewable and energy infrastructure projects. In addition, in 2014 Con Edison formed Consolidated Edison Transmission LLC (Con Edison Transmission) to invest in a transmission company. See information about Con Edison Transmission under “Guarantees” in Note H.
CECONY [Member]
General	General These combined notes accompany and form an integral part of the separate consolidated financial statements of each of the two separate registrants: Consolidated Edison, Inc. and its subsidiaries (Con Edison) and Consolidated Edison Company of New York, Inc. and its subsidiaries (CECONY). CECONY is a subsidiary of Con Edison and as such its financial condition and results of operations and cash flows, which are presented separately in the CECONY consolidated financial statements, are also consolidated, along with those of Con Edison’s other utility subsidiary, Orange and Rockland Utilities, Inc. (O&R) and Con Edison’s competitive energy businesses (discussed below) in Con Edison’s consolidated financial statements. The term “Utilities” is used in these notes to refer to CECONY and O&R. As used in these notes, the term “Companies” refers to Con Edison and CECONY and, except as otherwise noted, the information in these combined notes relates to each of the Companies. However, CECONY makes no representation as to information relating to Con Edison or the subsidiaries of Con Edison other than itself. The separate interim consolidated financial statements of each of the Companies are unaudited but, in the opinion of their respective managements, reflect all adjustments (which include only normally recurring adjustments) necessary for a fair presentation of the results for the interim periods presented. The Companies’ separate interim consolidated financial statements should be read together with their separate audited financial statements (including the combined notes thereto) included in Item 8 of their combined Annual Report on Form 10-K for the year ended December 31, 2014. Con Edison has two regulated utility subsidiaries: CECONY and O&R. CECONY provides electric service and gas service in New York City and Westchester County. The company also provides steam service in parts of Manhattan. O&R, along with its regulated utility subsidiaries, provides electric service in southeastern New York and adjacent areas of northern New Jersey and eastern Pennsylvania and gas service in southeastern New York and adjacent areas of eastern Pennsylvania. Con Edison has the following competitive energy businesses: Consolidated Edison Solutions, Inc. (Con Edison Solutions), a company which sells to retail customers electricity purchased in wholesale markets, enters into related hedging transactions and also provides energy-related products and services to retail customers; Consolidated Edison Energy, Inc. (Con Edison Energy), a company that provides energy-related products and services to wholesale customers; and Consolidated Edison Development, Inc. (Con Edison Development), a company that develops, owns and operates renewable and energy infrastructure projects. In addition, in 2014 Con Edison formed Consolidated Edison Transmission LLC (Con Edison Transmission) to invest in a transmission company. See information about Con Edison Transmission under “Guarantees” in Note H.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2015

Summary of Significant Accounting Policies

Note A – Summary of Significant Accounting Policies

Earnings Per Common Share

For the three months ended March 31, 2015 and 2014, basic and diluted earnings per share (EPS) for Con Edison are calculated as follows:


*(Millions of Dollars, except per share amounts/Shares in Millions)*	2015		2014
Net income for common stock		$370		$361
Weighted average common shares outstanding – basic		292.9		292.9
Add: Incremental shares attributable to effect of potentially dilutive securities		1.0		1.2
Adjusted weighted average common shares outstanding – diluted		293.9		294.1
Net Income for common stock per common share – basic		$1.26		$1.23
Net Income for common stock per common share – diluted		$1.26		$1.23

The computation of diluted EPS for the three months ended March 31, 2015 and 2014 exclude immaterial amounts of performance share awards that were not included because of their anti-dilutive effect.

Changes in Accumulated Other Comprehensive Income/(Loss) by Component

For the three months ended March 31, 2015 and 2014, changes to accumulated other comprehensive income/(loss) (OCI) for Con Edison and CECONY are as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance, accumulated OCI, net of taxes (b)		$(45	)		$(25	)		$(11	)		$(6	)
OCI before reclassifications, net of tax of $(2) and $(1) in 2015 and 2014, respectively, for Con Edison		3			2			—			—
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax of $(1) and $(1) in 2015 and 2014, respectively, for Con Edison (a)(b)		2			2			—			1
Current Period OCI, net of taxes		5			4			—			1
Ending balance, accumulated OCI, net of taxes		$(40	)		$(21	)		$(11	)		$(5	)

(a)

For the portion of unrecognized pension and other postretirement benefit costs relating to the regulated Utilities, costs are recorded into, and amortized out of, regulatory assets instead of OCI. The net actuarial losses and prior service costs recognized during the period are included in the computation of net periodic pension and other postretirement benefit cost. See Notes E and F.

(b)	Tax reclassified from accumulated OCI is reported in the income tax expense line item of the income statement.

CECONY [Member]

Summary of Significant Accounting Policies

Note A – Summary of Significant Accounting Policies

Earnings Per Common Share

For the three months ended March 31, 2015 and 2014, basic and diluted earnings per share (EPS) for Con Edison are calculated as follows:


*(Millions of Dollars, except per share amounts/Shares in Millions)*	2015		2014
Net income for common stock		$370		$361
Weighted average common shares outstanding – basic		292.9		292.9
Add: Incremental shares attributable to effect of potentially dilutive securities		1.0		1.2
Adjusted weighted average common shares outstanding – diluted		293.9		294.1
Net Income for common stock per common share – basic		$1.26		$1.23
Net Income for common stock per common share – diluted		$1.26		$1.23

The computation of diluted EPS for the three months ended March 31, 2015 and 2014 exclude immaterial amounts of performance share awards that were not included because of their anti-dilutive effect.

Changes in Accumulated Other Comprehensive Income/(Loss) by Component

For the three months ended March 31, 2015 and 2014, changes to accumulated other comprehensive income/(loss) (OCI) for Con Edison and CECONY are as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance, accumulated OCI, net of taxes (b)		$(45	)		$(25	)		$(11	)		$(6	)
OCI before reclassifications, net of tax of $(2) and $(1) in 2015 and 2014, respectively, for Con Edison		3			2			—			—
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax of $(1) and $(1) in 2015 and 2014, respectively, for Con Edison (a)(b)		2			2			—			1
Current Period OCI, net of taxes		5			4			—			1
Ending balance, accumulated OCI, net of taxes		$(40	)		$(21	)		$(11	)		$(5	)

(a)

(b)	Tax reclassified from accumulated OCI is reported in the income tax expense line item of the income statement.

- Definition

The entire disclosure for all significant accounting policies of the reporting entity.

+ References+ Details

Regulatory Matters

3 Months Ended

Mar. 31, 2015

Regulatory Matters

Note B — Regulatory Matters

Rate Plans

CECONY — Electric

On April 20, 2015, CECONY entered into a Joint Proposal with the staff of the New York State Public Service Commission (NYSPSC) and other parties for the extension of CECONY’s current electric rate plan for an additional year through 2016. Under the Joint Proposal, which is subject to NYSPSC approval, the rate plan for 2016 does not include a rate increase or decrease. The rate plan for 2016 includes additional revenues from the amortization to income of net regulatory liabilities. The following table contains a summary of the rate plan for 2016:


Effective period		January 2016 – December 2016
Base rate changes		None (a)
Amortizations to income of net regulatory (assets) liabilities		Additional $123 million of net regulatory liabilities (b)
Other revenue sources		Continued retention of $90 million of annual transmission congestion revenues
Revenue decoupling mechanism		Continued reconciliation of actual electric delivery revenues to those authorized in the rate plan
Recoverable energy costs		Continued current rate recovery of purchased power and fuel costs
Negative revenue adjustments		Continued potential for penalties of up to $400 million if certain performance targets are not met
Cost reconciliations		Continued reconciliation of expenses for pension and other postretirement benefits, variable-rate tax-exempt debt, major storms, property taxes (c), municipal infrastructure support, the impact of new laws and environmental remediation to amounts reflected in rates
Net utility plant reconciliations		Target levels reflected in rates are as follows: Transmission and distribution: $17,929 million Storm hardening: $268 million Other: $2,069 million
Average rate base		$18,282 million
Weighted average cost of capital (after-tax)		6.91 percent
Authorized return on common equity		9.0 percent
Earnings sharing		Most earnings above an annual earnings threshold of 9.6 percent are to be applied to reduce regulatory assets for environmental remediation and other costs
Cost of long-term debt		5.09 percent
Common equity ratio		48 percent

(a)

The impact of 2014 and 2015 base rate changes under the current electric rate plan will continue to be deferred. $249 million of annual revenues collected from electric customers will continue to be subject to potential refund following NYSPSC staff review of certain costs. Revenues will continue to include $21 million as funding for major storm reserve.

(b)

The Joint Proposal also provides for continued annual amortization of $107 million of the regulatory asset for deferred Superstorm Sandy and other major storm costs and recommends that the costs recoverable from customers be reduced by $4 million, the costs no longer be subject to NYSPSC staff review and the recovery of the costs no longer be subject to refund.

(c)	Deferrals for property taxes will continue to be limited to 90 percent of the difference from amounts reflected in rates, subject to an annual maximum for the remaining difference of not more than a 10 basis point impact on return on common equity.

O&R New York – Electric and Gas

In March 2015, in O&R’s electric and gas rate proceedings, NYSPSC staff recommended a $0.6 million decrease in O&R’s electric rates and a $14.7 million increase in its gas rates (reflecting an authorized return on common equity of 8.5 percent). In April 2015, O&R submitted updated requests to the NYSPSC for increases in its electric and gas rates of $34 million and $44.2 million, respectively (reflecting an authorized return on common equity of 9.75 percent).

Other Regulatory Matters

In February 2009, the NYSPSC commenced a proceeding to examine the prudence of certain CECONY expenditures following the arrests of employees for accepting illegal payments from a construction contractor. Subsequently, additional employees were arrested for accepting illegal payments from materials suppliers and an engineering firm. The arrested employees were terminated by the company and have pled guilty or been convicted. Pursuant to NYSPSC orders, a portion of the company’s revenues (currently, $249 million, $32 million and $6 million on an annual basis for electric, gas and steam service, respectively) is being collected subject to potential refund to customers. The amount of electric revenues collected subject to refund, which was established in a different proceeding, and the amount of gas and steam revenues collected subject to refund were not established as indicative of the company’s potential liability in this proceeding. At March 31, 2015, the company had collected an estimated $1,747 million from customers subject to potential refund in connection with this proceeding. In January 2013, a NYSPSC consultant reported its estimate, with which the company does not agree, of $208 million of overcharges with respect to a substantial portion of the company’s construction expenditures from January 2000 to January 2009. The company is disputing the consultant’s estimate, including its determinations as to overcharges regarding specific construction expenditures it selected to review and its methodology of extrapolating such determinations over a substantial portion of the construction expenditures during this period. The NYSPSC’s consultant has not reviewed the company’s other expenditures. The company and NYSPSC staff are exploring a settlement in this proceeding. In May 2014, the NYSPSC’s Chief Administrative Law Judge appointed a settlement judge to assist the parties. There is no assurance that there will be a settlement, and any settlement would be subject to NYSPSC approval. At March 31, 2015, the company had a $104 million regulatory liability relating to this matter. The company currently estimates that any additional amount the NYSPSC requires the company to refund to customers in excess of the regulatory liability accrued could range up to an amount based on the NYSPSC consultant’s $208 million estimate of overcharges.

In late October 2012, Superstorm Sandy caused extensive damage to the Utilities’ electric distribution system and interrupted service to approximately 1.4 million customers. Superstorm Sandy also damaged CECONY’s steam system and interrupted service to many of its steam customers. As of March 31, 2015, CECONY and O&R incurred response and restoration costs for Superstorm Sandy of $506 million and $91 million, respectively (including capital expenditures of $148 million and $15 million, respectively). Most of the costs that were not capitalized were deferred for recovery as a regulatory asset under the Utilities’ electric rate plans. See “Regulatory Assets and Liabilities” below. CECONY’s current electric rate plan includes collection from customers of deferred storm costs (including for Superstorm Sandy), subject to refund following NYSPSC review of the costs. Pursuant to the April 2015 Joint Proposal with respect to CECONY’s electric rates, which is subject to NYSPSC approval, the deferred storm costs recoverable from customers will be reduced by $4 million, the costs will no longer be subject to NYSPSC staff review and recovery of the costs will no longer be subject to refund. As part of its rate filing, in November 2014 O&R requested recovery of deferred storm costs for its New York electric operations, which are subject to NYSPSC review. RECO’s current electric rate plan includes collection from customers of deferred storm costs.

In June 2014, the NYSPSC initiated a proceeding to investigate the practices of qualifying persons to perform plastic fusions on gas facilities. New York State regulations require gas utilities to qualify and, except in certain circumstances, annually requalify workers that perform fusion to join plastic pipe. The NYSPSC directed the New York gas utilities to provide information in this proceeding about their compliance with the qualification and requalification requirements and related matters; their procedures for compliance with all gas safety regulations; and their annual chief executive officer certifications regarding these and other procedures. CECONY’s qualification and requalification procedures had not included certain required testing to evaluate specimen fuses. In addition, CECONY and O&R had not timely requalified certain workers that had been qualified under their respective procedures to perform fusion to join plastic pipe. CECONY and O&R have requalified their workers who perform plastic pipe fusions. In April 2015, the NYSPSC issued a notice seeking the sampling plans CECONY, O&R and other gas utilities intend to use to inspect and test plastic pipe fusions. The notice also included NYSPSC staff proposals to require these utilities to perform remediation plans, additional leakage surveying and reporting; to require CECONY to hire an independent statistician to develop a risk assessment and remediation plan; and for certain new plastic fusion requirements for gas utilities.

Regulatory Assets and Liabilities

Regulatory assets and liabilities at March 31, 2015 and December 31, 2014 were comprised of the following items:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Regulatory assets
Unrecognized pension and other postretirement costs	$	4,593	$	4,846	$	4,374	$	4,609
Future income tax		2,289		2,273		2,180		2,166
Environmental remediation costs		911		925		808		820
Deferred storm costs		287		319		196		224
Revenue taxes		223		219		211		208
Surcharge for New York State assessment		96		99		90		92
Pension and other postretirement benefits deferrals		61		66		35		42
Net electric deferrals		58		63		58		63
Unamortized loss on reacquired debt		56		57		53		55
Deferred derivative losses – noncurrent		44		25		40		23
Recoverable energy costs – noncurrent		42		19		42		17
O&R property tax reconciliation		40		36		—		—
O&R transition bond charges		25		27		—		—
Preferred stock redemption		27		27		27		27
Workers’ compensation		9		8		9		8
Other		145		147		128		127
Regulatory assets – noncurrent		8,906		9,156		8,251		8,481
Deferred derivative losses – current		55		97		51		92
Future income tax – current		10		10		—		—
Recoverable energy costs – current		1		41		—		40
Regulatory assets – current		66		148		51		132
Total Regulatory Assets	$	8,972	$	9,304	$	8,302	$	8,613
Regulatory liabilities
Allowance for cost of removal less salvage	$	614	$	598	$	514	$	499
Property tax reconciliation		297		295		297		295
Base rate change deferrals		153		155		153		155
Prudence proceeding		104		105		104		105
Pension and other postretirement benefit deferrals		85		46		64		37
Property tax refunds		76		87		76		87
Variable-rate tax-exempt debt – cost rate reconciliation		74		78		74		78
Net unbilled revenue deferrals		71		138		71		138
New York State income tax rate change		63		62		60		59
Carrying charges on repair allowance and bonus depreciation		52		58		50		57
World Trade Center settlement proceeds		36		41		36		41
Net utility plant reconciliations		21		21		21		20
Earnings sharing – electric		19		19		18		18
Unrecognized other postretirement costs		15		—		13		—
Other		212		290		177		248
Regulatory liabilities – noncurrent		1,892		1,993		1,728		1,837
Refundable energy costs – current		177		128		152		84
Revenue decoupling mechanism		30		30		30		30
Future income tax		25		24		24		24
Deferred derivative gains – current		8		5		6		4
Regulatory liabilities – current		240		187		212		142
Total Regulatory Liabilities	$	2,132	$	2,180	$	1,940	$	1,979

CECONY [Member]

Regulatory Matters

Note B — Regulatory Matters

Rate Plans

CECONY — Electric


Effective period		January 2016 – December 2016
Base rate changes		None (a)
Amortizations to income of net regulatory (assets) liabilities		Additional $123 million of net regulatory liabilities (b)
Other revenue sources		Continued retention of $90 million of annual transmission congestion revenues
Revenue decoupling mechanism		Continued reconciliation of actual electric delivery revenues to those authorized in the rate plan
Recoverable energy costs		Continued current rate recovery of purchased power and fuel costs
Negative revenue adjustments		Continued potential for penalties of up to $400 million if certain performance targets are not met
Cost reconciliations		Continued reconciliation of expenses for pension and other postretirement benefits, variable-rate tax-exempt debt, major storms, property taxes (c), municipal infrastructure support, the impact of new laws and environmental remediation to amounts reflected in rates
Net utility plant reconciliations		Target levels reflected in rates are as follows: Transmission and distribution: $17,929 million Storm hardening: $268 million Other: $2,069 million
Average rate base		$18,282 million
Weighted average cost of capital (after-tax)		6.91 percent
Authorized return on common equity		9.0 percent
Earnings sharing		Most earnings above an annual earnings threshold of 9.6 percent are to be applied to reduce regulatory assets for environmental remediation and other costs
Cost of long-term debt		5.09 percent
Common equity ratio		48 percent

(a)

(b)

(c)	Deferrals for property taxes will continue to be limited to 90 percent of the difference from amounts reflected in rates, subject to an annual maximum for the remaining difference of not more than a 10 basis point impact on return on common equity.

O&R New York – Electric and Gas

Other Regulatory Matters

Regulatory Assets and Liabilities

Regulatory assets and liabilities at March 31, 2015 and December 31, 2014 were comprised of the following items:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Regulatory assets
Unrecognized pension and other postretirement costs	$	4,593	$	4,846	$	4,374	$	4,609
Future income tax		2,289		2,273		2,180		2,166
Environmental remediation costs		911		925		808		820
Deferred storm costs		287		319		196		224
Revenue taxes		223		219		211		208
Surcharge for New York State assessment		96		99		90		92
Pension and other postretirement benefits deferrals		61		66		35		42
Net electric deferrals		58		63		58		63
Unamortized loss on reacquired debt		56		57		53		55
Deferred derivative losses – noncurrent		44		25		40		23
Recoverable energy costs – noncurrent		42		19		42		17
O&R property tax reconciliation		40		36		—		—
O&R transition bond charges		25		27		—		—
Preferred stock redemption		27		27		27		27
Workers’ compensation		9		8		9		8
Other		145		147		128		127
Regulatory assets – noncurrent		8,906		9,156		8,251		8,481
Deferred derivative losses – current		55		97		51		92
Future income tax – current		10		10		—		—
Recoverable energy costs – current		1		41		—		40
Regulatory assets – current		66		148		51		132
Total Regulatory Assets	$	8,972	$	9,304	$	8,302	$	8,613
Regulatory liabilities
Allowance for cost of removal less salvage	$	614	$	598	$	514	$	499
Property tax reconciliation		297		295		297		295
Base rate change deferrals		153		155		153		155
Prudence proceeding		104		105		104		105
Pension and other postretirement benefit deferrals		85		46		64		37
Property tax refunds		76		87		76		87
Variable-rate tax-exempt debt – cost rate reconciliation		74		78		74		78
Net unbilled revenue deferrals		71		138		71		138
New York State income tax rate change		63		62		60		59
Carrying charges on repair allowance and bonus depreciation		52		58		50		57
World Trade Center settlement proceeds		36		41		36		41
Net utility plant reconciliations		21		21		21		20
Earnings sharing – electric		19		19		18		18
Unrecognized other postretirement costs		15		—		13		—
Other		212		290		177		248
Regulatory liabilities – noncurrent		1,892		1,993		1,728		1,837
Refundable energy costs – current		177		128		152		84
Revenue decoupling mechanism		30		30		30		30
Future income tax		25		24		24		24
Deferred derivative gains – current		8		5		6		4
Regulatory liabilities – current		240		187		212		142
Total Regulatory Liabilities	$	2,132	$	2,180	$	1,940	$	1,979

Capitalization

3 Months Ended

Mar. 31, 2015

Capitalization

Note C — Capitalization

The carrying amounts and fair values of long-term debt at March 31, 2015 and December 31, 2014 are:


*(Millions of Dollars)*	2015				2014
Long-Term Debt (including current portion)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Con Edison		$12,190		$14,224		$12,191		$13,998
CECONY		$11,214		$13,066		$11,214		$12,846

Fair values of long-term debt have been estimated primarily using available market information. For Con Edison, $13,588 million and $636 million of the fair value of long-term debt at March 31, 2015 are classified as Level 2 and Level 3, respectively. For CECONY, $12,430 million and $636 million of the fair value of long-term debt at March 31, 2015 are classified as Level 2 and Level 3, respectively (see Note L). The $636 million of long-term debt classified as Level 3 is CECONY’s tax-exempt, auction-rate securities for which the market is highly illiquid and there is a lack of observable inputs.

CECONY [Member]

Capitalization

Note C — Capitalization

The carrying amounts and fair values of long-term debt at March 31, 2015 and December 31, 2014 are:


*(Millions of Dollars)*	2015				2014
Long-Term Debt (including current portion)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Con Edison		$12,190		$14,224		$12,191		$13,998
CECONY		$11,214		$13,066		$11,214		$12,846

Short-Term Borrowing	3 Months Ended
Short-Term Borrowing	Mar. 31, 2015
Short-Term Borrowing	Note D — Short-Term Borrowing At March 31, 2015, Con Edison had $519 million of commercial paper outstanding of which $268 million was outstanding under CECONY’s program. The weighted average interest rate at March 31, 2015 was 0.5 percent for both Con Edison and CECONY. At December 31, 2014, Con Edison had $800 million of commercial paper outstanding of which $450 million was outstanding under CECONY’s program. The weighted average interest rate at December 31, 2014 was 0.4 percent for both Con Edison and CECONY. At March 31, 2015 and December 31, 2014, no loans were outstanding under the credit agreement (Credit Agreement) and $61 million (including $11 million for CECONY) and $11 million (including $11 million for CECONY), respectively, of letters of credit were outstanding under the Credit Agreement.
CECONY [Member]
Short-Term Borrowing	Note D — Short-Term Borrowing At March 31, 2015, Con Edison had $519 million of commercial paper outstanding of which $268 million was outstanding under CECONY’s program. The weighted average interest rate at March 31, 2015 was 0.5 percent for both Con Edison and CECONY. At December 31, 2014, Con Edison had $800 million of commercial paper outstanding of which $450 million was outstanding under CECONY’s program. The weighted average interest rate at December 31, 2014 was 0.4 percent for both Con Edison and CECONY. At March 31, 2015 and December 31, 2014, no loans were outstanding under the credit agreement (Credit Agreement) and $61 million (including $11 million for CECONY) and $11 million (including $11 million for CECONY), respectively, of letters of credit were outstanding under the Credit Agreement.

- Definition

The entire disclosure for short-term debt.

+ References+ Details

Pension Benefits

3 Months Ended

Mar. 31, 2015

Pension Benefits

Note E — Pension Benefits

Total Periodic Benefit Cost

The components of the Companies’ total periodic benefit costs for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Service cost – including administrative expenses	$	74		$	57		$	70		$	53
Interest cost on projected benefit obligation		144			143			135			134
Expected return on plan assets		(222	)		(208	)		(210	)		(197	)
Recognition of net actuarial loss		194			154			183			146
Recognition of prior service costs		1			1			—			1
TOTAL PERIODIC BENEFIT COST	$	191		$	147		$	178		$	137
Cost capitalized		(68	)		(51	)		(65	)		(49	)
Reconciliation to rate level		(24	)		26			(24	)		23
Cost charged to operating expenses	$	99		$	122		$	89		$	111

Expected Contributions

Based on estimates as of March 31, 2015, the Companies expect to make contributions to the pension plans during 2015 of $750 million (of which $697 million is to be contributed by CECONY) and $16 million to the CECONY external trust for supplemental retirement plans. The Companies’ policy is to fund the total periodic benefit cost of the qualified plan to the extent tax deductible and to also contribute to the non-qualified plans. During the first quarter of 2015, the Companies contributed $204 million to the pension plans, nearly all of which was contributed by CECONY.

CECONY [Member]

Pension Benefits

Note E — Pension Benefits

Total Periodic Benefit Cost

The components of the Companies’ total periodic benefit costs for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Service cost – including administrative expenses	$	74		$	57		$	70		$	53
Interest cost on projected benefit obligation		144			143			135			134
Expected return on plan assets		(222	)		(208	)		(210	)		(197	)
Recognition of net actuarial loss		194			154			183			146
Recognition of prior service costs		1			1			—			1
TOTAL PERIODIC BENEFIT COST	$	191		$	147		$	178		$	137
Cost capitalized		(68	)		(51	)		(65	)		(49	)
Reconciliation to rate level		(24	)		26			(24	)		23
Cost charged to operating expenses	$	99		$	122		$	89		$	111

Expected Contributions

- Definition

The entire disclosure for pension and other postretirement benefits.

+ References+ Details

Other Postretirement Benefits

3 Months Ended

Mar. 31, 2015

Other Postretirement Benefits

Note F — Other Postretirement Benefits

Total Periodic Benefit Cost

The components of the Companies’ total periodic other postretirement benefit costs for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Service cost	$	5		$	5		$	4		$	4
Interest cost on accumulated other postretirement benefit obligation		13			15			11			13
Expected return on plan assets		(20	)		(19	)		(17	)		(17	)
Recognition of net actuarial loss		8			14			7			13
Recognition of prior service cost		(5	)		(5	)		(4	)		(4	)
TOTAL PERIODIC OTHER POSTRETIREMENT BENEFIT COST	$	1		$	10		$	1		$	9
Cost capitalized		(1	)		(4	)		(1	)		(3	)
Reconciliation to rate level		4			3			2			—
Cost charged to operating expenses	$	4		$	9		$	2		$	6

Expected Contributions

Based on estimates as of March 31, 2015, Con Edison expects to make a contribution of $6 million, nearly all of which is for CECONY, to the other postretirement benefit plans in 2015.

Environmental Matters

3 Months Ended

Mar. 31, 2015

Environmental Matters

Note G — Environmental Matters

Superfund Sites

Hazardous substances, such as asbestos, polychlorinated biphenyls (PCBs) and coal tar, have been used or generated in the course of operations of the Utilities and their predecessors and are present at sites and in facilities and equipment they currently or previously owned, including sites at which gas was manufactured or stored.

The Federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 and similar state statutes (Superfund) impose joint and several liability, regardless of fault, upon generators of hazardous substances for investigation and remediation costs (which include costs of demolition, removal, disposal, storage, replacement, containment and monitoring) and natural resource damages. Liability under these laws can be material and may be imposed for contamination from past acts, even though such past acts may have been lawful at the time they occurred. The sites at which the Utilities have been asserted to have liability under these laws, including their manufactured gas plant sites and any neighboring areas to which contamination may have migrated, are referred to herein as “Superfund Sites.”

For Superfund Sites where there are other potentially responsible parties and the Utilities are not managing the site investigation and remediation, the accrued liability represents an estimate of the amount the Utilities will need to pay to investigate and, where determinable, discharge their related obligations. For Superfund Sites (including the manufactured gas plant sites) for which one of the Utilities is managing the investigation and remediation, the accrued liability represents an estimate of the company’s share of the undiscounted cost to investigate the sites and, for sites that have been investigated in whole or in part, the cost to remediate the sites, if remediation is necessary and if a reasonable estimate of such cost can be made. Remediation costs are estimated in light of the information available, applicable remediation standards and experience with similar sites.

The accrued liabilities and regulatory assets related to Superfund Sites at March 31, 2015 and December 31, 2014 were as follows:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued Liabilities:
Manufactured gas plant sites		$678		$684		$582		$587
Other Superfund Sites		80		80		80		79
Total		$758		$764		$662		$666
Regulatory assets		$911		$925		$808		$820

Most of the accrued Superfund Site liability relates to sites that have been investigated, in whole or in part. However, for some of the sites, the extent and associated cost of the required remediation has not yet been determined. As investigations progress and information pertaining to the required remediation becomes available, the Utilities expect that additional liability may be accrued, the amount of which is not presently determinable but may be material. The Companies are unable to estimate the time period over which the remaining accrued liability will be incurred because, among other things, the required remediation has not been determined for some of the sites. Under their current rate plans, the Utilities are permitted to recover or defer as regulatory assets (for subsequent recovery through rates) certain site investigation and remediation costs.

Environmental remediation costs incurred and insurance recoveries received related to Superfund Sites for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison				CECONY
(Millions of Dollars)	2015		2014		2015		2014
Remediation costs incurred		$7		$9		$6		$8
Insurance recoveries received*		—		5		—		5
* Reduced amount deferred for recovery from customers

In 2014, Con Edison and CECONY estimated that for their manufactured gas plant sites (including CECONY’s Astoria site), the aggregate undiscounted potential liability for the investigation and remediation of coal tar and/or other environmental contaminants could range up to $2.7 billion and $2.5 billion, respectively. These estimates were based on the assumption that there is contamination at all sites, including those that have not yet been fully investigated and additional assumptions about the extent of the contamination and the type and extent of the remediation that may be required. Actual experience may be materially different.

Asbestos Proceedings

Suits have been brought in New York State and federal courts against the Utilities and many other defendants, wherein a large number of plaintiffs sought large amounts of compensatory and punitive damages for deaths and injuries allegedly caused by exposure to asbestos at various premises of the Utilities. The suits that have been resolved, which are many, have been resolved without any payment by the Utilities, or for amounts that were not, in the aggregate, material to them. The amounts specified in all the remaining thousands of suits total billions of dollars; however, the Utilities believe that these amounts are greatly exaggerated, based on the disposition of previous claims. At March 31, 2015, Con Edison and CECONY had accrued their estimated aggregate undiscounted potential liabilities for these suits and additional suits that may be brought over the next 15 years of $8 million and $7 million, respectively. The estimates were based upon a combination of modeling, historical data analysis and risk factor assessment. Trial courts have begun, and unless otherwise determined by an appellate court may continue, to apply a different standard for determining liability in asbestos suits than the standard that applied historically. As a result, the Companies currently believe that there is a reasonable possibility of an exposure to loss in excess of the liability accrued for the suits. The Companies are unable to estimate the amount or range of such loss. In addition, certain current and former employees have claimed or are claiming workers’ compensation benefits based on alleged disability from exposure to asbestos. Under its current rate plans, CECONY is permitted to defer as regulatory assets (for subsequent recovery through rates) costs incurred for its asbestos lawsuits and workers’ compensation claims.

The accrued liability for asbestos suits and workers’ compensation proceedings (including those related to asbestos exposure) and the amounts deferred as regulatory assets for the Companies at March 31, 2015 and December 31, 2014 were as follows:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued liability – asbestos suits	$	8	$	8	$	7	$	7
Regulatory assets – asbestos suits	$	8	$	8	$	7	$	7
Accrued liability – workers’ compensation	$	84	$	83	$	79	$	78
Regulatory assets – workers’ compensation	$	9	$	8	$	9	$	8

CECONY [Member]

Environmental Matters

Note G — Environmental Matters

Superfund Sites

The accrued liabilities and regulatory assets related to Superfund Sites at March 31, 2015 and December 31, 2014 were as follows:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued Liabilities:
Manufactured gas plant sites		$678		$684		$582		$587
Other Superfund Sites		80		80		80		79
Total		$758		$764		$662		$666
Regulatory assets		$911		$925		$808		$820

Environmental remediation costs incurred and insurance recoveries received related to Superfund Sites for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison				CECONY
(Millions of Dollars)	2015		2014		2015		2014
Remediation costs incurred		$7		$9		$6		$8
Insurance recoveries received*		—		5		—		5
* Reduced amount deferred for recovery from customers

Asbestos Proceedings


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued liability – asbestos suits	$	8	$	8	$	7	$	7
Regulatory assets – asbestos suits	$	8	$	8	$	7	$	7
Accrued liability – workers’ compensation	$	84	$	83	$	79	$	78
Regulatory assets – workers’ compensation	$	9	$	8	$	9	$	8

- Definition

The entire disclosure for environmental loss contingencies, such as presence of hazardous waste, relevant information from reports issued by regulators, and estimated costs to achieve compliance with regulatory requirements. This element may be used for all of an entity's disclosures about environmental loss contingencies.

+ References+ Details

Other Material Contingencies

3 Months Ended

Mar. 31, 2015

Other Material Contingencies

Note H — Other Material Contingencies

Manhattan Steam Main Rupture

In July 2007, a CECONY steam main located in midtown Manhattan ruptured. It has been reported that one person died and others were injured as a result of the incident. Several buildings in the area were damaged. Debris from the incident included dirt and mud containing asbestos. The response to the incident required the closing of several buildings and streets for various periods. Approximately ninety suits are pending against the company seeking generally unspecified compensatory and, in some cases, punitive damages, for personal injury, property damage and business interruption. The company has notified its insurers of the incident and believes that the policies in force at the time of the incident will cover the company’s costs to satisfy its liability to others in connection with the suits. In the company’s estimation, there is not a reasonable possibility that an exposure to loss exists for the suits that is materially in excess of the estimated liability accrued. At March 31, 2015, the company has accrued its estimated liability for the suits of $50 million and an insurance receivable in the same amount.

Manhattan Explosion and Fire

On March 12, 2014, two multi-use five-story tall buildings located on Park Avenue between 116^th and 117^th Street in Manhattan were destroyed by an explosion and fire. CECONY had delivered gas to the buildings through service lines from a distribution main located below ground on Park Avenue. Eight people died and more than 48 people were injured. Additional buildings were also damaged. The National Transportation Safety Board (NTSB) is investigating. The parties to the investigation include the company, the City of New York, the Pipeline and Hazardous Materials Safety Administration and the NYSPSC (which is also conducting an investigation). In March 2015, the NTSB issued reports on: operations, emergency preparedness and emergency response of the company and certain City departments; testing of company plastic pipe and its fusion and City water main; the company’s public awareness program; and regulatory oversight. It is expected that the NTSB will be issuing a final report concerning the incident, its probable cause and safety recommendations. Approximately 35 suits are pending against the company seeking generally unspecified damages and, in one case, punitive damages, for personal injury, property damage and business interruption. The company has notified its insurers of the incident and believes that the policies in force at the time of the incident will cover the company’s costs, in excess of a required retention (the amount of which is not material), to satisfy any liability it may have for damages in connection with the incident. The company is unable to estimate the amount or range of its possible loss related to the incident. At March 31, 2015, the company had not accrued a liability for the incident.

Other Contingencies

See “Other Regulatory Matters” in Note B and “Uncertain Tax Positions” in Note I.

Guarantees

Con Edison and its subsidiaries enter into various agreements providing financial or performance assurance primarily to third parties on behalf of their subsidiaries. Maximum amounts guaranteed by Con Edison totaled $2,559 million and $2,547 million at March 31, 2015 and December 31, 2014, respectively.

A summary, by type and term, of Con Edison’s total guarantees at March 31, 2015 is as follows:


Guarantee Type	0 – 3 years		4 – 10 years		> 10 years		Total
	*(Millions of Dollars)*
NY Transco		$1,360		$—		$—		$1,360
Energy transactions		830		38		90		958
Renewable electric production projects		204		—		7		211
Other		30		—		—		30
Total		$2,424		$38		$97		$2,559

NY Transco — Con Edison has guaranteed payment by its subsidiary, Con Edison Transmission, of the contributions it agreed to make in New York Transco LLC (NY Transco). Con Edison Transmission acquired a 45.7 percent interest in NY Transco when it was formed in 2014. NY Transco’s transmission projects areexpected to be developed initially by CECONY and other New York transmission owners and then sold to NY Transco. The development of the projects wouldbe subject to authorizations from the NYSPSC, the Federal Energy Regulatory Commission and other federal, state and local agencies. Guarantee amount shown is for the maximum possible required amount of Con Edison Transmission’s contributions, which assumed that all the NY Transco projects proposed when NY Transco was formed receive all required regulatory approvals and are completed at 175 percent of their estimated costs and that NY Transco does not use any debt financing for the projects. Guarantee term shown is assumed as the timing of the contributions is not known.

Energy Transactions — Con Edison guarantees payments on behalf of its competitive energy businesses in order to facilitate physical and financial transactions in gas, pipeline capacity, transportation, oil, electricity, renewable energy credits and energy services. To the extent that liabilities exist under the contracts subject to these guarantees, such liabilities are included in Con Edison’s consolidated balance sheet.

Renewable Electric Production Projects — Con Edison and Con Edison Development guarantee payments associated with the investment in solar and wind energy facilities on behalf of their wholly-owned subsidiaries. In addition, Con Edison Development has entered into two guarantees ($35 million maximum and $15 million maximum, respectively) on behalf of entities (Copper Mountain Solar 2 and Copper Mountain Solar 3, respectively) in which it has a 50 percent interest in connection with the construction of solar energy facilities. Con Edison Development also provided $3 million in guarantees to Travelers Insurance Company for indemnity agreements for surety bonds in connection with the construction and operation of solar energy facilities performed by its subsidiaries.

Other — Other guarantees primarily relate to guarantees provided by Con Edison to Travelers Insurance Company for indemnity agreements for surety bonds in connection with energy service projects performed by Con Edison Solutions ($25 million). In addition, Con Edison issued a guarantee to the Public Utility Commission of Texas covering obligations of Con Edison Solutions as a retail electric provider. Con Edison’s estimate of the maximum potential obligation for this guarantee is $5 million as of March 31, 2015.

CECONY [Member]

Other Material Contingencies

Note H — Other Material Contingencies

Manhattan Steam Main Rupture

Manhattan Explosion and Fire

Other Contingencies

See “Other Regulatory Matters” in Note B and “Uncertain Tax Positions” in Note I.

Guarantees

A summary, by type and term, of Con Edison’s total guarantees at March 31, 2015 is as follows:


Guarantee Type	0 – 3 years		4 – 10 years		> 10 years		Total
	*(Millions of Dollars)*
NY Transco		$1,360		$—		$—		$1,360
Energy transactions		830		38		90		958
Renewable electric production projects		204		—		7		211
Other		30		—		—		30
Total		$2,424		$38		$97		$2,559

- Definition

The entire disclosure for commitments and contingencies.

+ References+ Details

Income Tax	3 Months Ended
Income Tax	Mar. 31, 2015
Income Tax	Note I — Income Tax Con Edison’s income tax expense increased to $199 million for the three months ended March 31, 2015 from $198 million for the three months ended March 31, 2014. The effective tax rate for the three months ended March 31, 2015 and 2014 was 35 percent. CECONY’s income tax expense increased to $192 million for the three months ended March 31, 2015 from $184 million for the three months ended March 31, 2014. The effective tax rate for the three months ended March 31, 2015 and 2014 was 36 percent. Uncertain Tax Positions At March 31, 2015, the estimated liability for uncertain tax positions for Con Edison was $34 million ($2 million for CECONY). Con Edison reasonably expects to resolve approximately $25 million ($16 million, net of federal taxes) of its uncertain tax positions within the next twelve months, of which the entire amount, if recognized, would reduce Con Edison’s effective tax rate. The amount related to CECONY is approximately $2 million ($1 million, net of federal taxes), of which the entire amount, if recognized, would reduce CECONY’s effective tax rate. The total amount of unrecognized tax benefits, if recognized, that would reduce Con Edison’s effective tax rate is $34 million ($22 million, net of federal taxes). The Companies recognize interest on liabilities for uncertain tax positions in interest expense and would recognize penalties, if any, in operating expenses in the Companies’ consolidated income statements. In the three months ended March 31, 2015, Con Edison recognized an immaterial amount of interest expense and no penalties for uncertain tax positions in its consolidated income statements. At March 31, 2015 and December 31, 2014, Con Edison recognized an immaterial amount of accrued interest on its consolidated balance sheets.
CECONY [Member]
Income Tax	Note I — Income Tax Con Edison’s income tax expense increased to $199 million for the three months ended March 31, 2015 from $198 million for the three months ended March 31, 2014. The effective tax rate for the three months ended March 31, 2015 and 2014 was 35 percent. CECONY’s income tax expense increased to $192 million for the three months ended March 31, 2015 from $184 million for the three months ended March 31, 2014. The effective tax rate for the three months ended March 31, 2015 and 2014 was 36 percent. Uncertain Tax Positions At March 31, 2015, the estimated liability for uncertain tax positions for Con Edison was $34 million ($2 million for CECONY). Con Edison reasonably expects to resolve approximately $25 million ($16 million, net of federal taxes) of its uncertain tax positions within the next twelve months, of which the entire amount, if recognized, would reduce Con Edison’s effective tax rate. The amount related to CECONY is approximately $2 million ($1 million, net of federal taxes), of which the entire amount, if recognized, would reduce CECONY’s effective tax rate. The total amount of unrecognized tax benefits, if recognized, that would reduce Con Edison’s effective tax rate is $34 million ($22 million, net of federal taxes). The Companies recognize interest on liabilities for uncertain tax positions in interest expense and would recognize penalties, if any, in operating expenses in the Companies’ consolidated income statements. In the three months ended March 31, 2015, Con Edison recognized an immaterial amount of interest expense and no penalties for uncertain tax positions in its consolidated income statements. At March 31, 2015 and December 31, 2014, Con Edison recognized an immaterial amount of accrued interest on its consolidated balance sheets.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References+ Details

Financial Information by Business Segment

3 Months Ended

Mar. 31, 2015

Financial Information by Business Segment

Note J — Financial Information by Business Segment

The financial data for the business segments are as follows:


	For the Three Months Ended March 31,
	Operating revenues					Inter-segment revenues						Depreciation and amortization				Operating income
	2015			2014		2015			2014			2015		2014		2015			2014
CECONY
Electric	$	1,980		$	2,074	$	4		$	4		$	202	$	189	$	279		$	257
Gas		655			789		1			1			35		32		241			233
Steam		375			341		22			20			20		19		164			153
Consolidation adjustments		—			—		(27	)		(25	)		—		—		—			—
Total CECONY	$	3,010		$	3,204	$	—		$	—		$	257	$	240	$	684		$	643
O&R
Electric	$	156		$	163	$	—		$	—		$	12	$	10	$	18		$	12
Gas		77			93		—			—			5		4		27			27
Total O&R	$	233		$	256	$	—		$	—		$	17	$	14	$	45		$	39
Competitive energy businesses	$	374		$	329	$	(3	)	$	3		$	5		7	$	(3	)	$	2
Other(a)		(1	)		—		3			(3	)		—		—		—			1
Total Con Edison	$	3,616		$	3,789	$	—		$	—		$	279	$	261	$	726		$	685

(a)	Parent company and consolidation adjustments. Other does not represent a business segment.

CECONY [Member]

Financial Information by Business Segment

Note J — Financial Information by Business Segment

The financial data for the business segments are as follows:


	For the Three Months Ended March 31,
	Operating revenues					Inter-segment revenues						Depreciation and amortization				Operating income
	2015			2014		2015			2014			2015		2014		2015			2014
CECONY
Electric	$	1,980		$	2,074	$	4		$	4		$	202	$	189	$	279		$	257
Gas		655			789		1			1			35		32		241			233
Steam		375			341		22			20			20		19		164			153
Consolidation adjustments		—			—		(27	)		(25	)		—		—		—			—
Total CECONY	$	3,010		$	3,204	$	—		$	—		$	257	$	240	$	684		$	643
O&R
Electric	$	156		$	163	$	—		$	—		$	12	$	10	$	18		$	12
Gas		77			93		—			—			5		4		27			27
Total O&R	$	233		$	256	$	—		$	—		$	17	$	14	$	45		$	39
Competitive energy businesses	$	374		$	329	$	(3	)	$	3		$	5		7	$	(3	)	$	2
Other(a)		(1	)		—		3			(3	)		—		—		—			1
Total Con Edison	$	3,616		$	3,789	$	—		$	—		$	279	$	261	$	726		$	685

(a)	Parent company and consolidation adjustments. Other does not represent a business segment.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Derivative Instruments and Hedging Activities

3 Months Ended

Mar. 31, 2015

Derivative Instruments and Hedging Activities

Note K — Derivative Instruments and Hedging Activities

Con Edison’s subsidiaries hedge market price fluctuations associated with physical purchases and sales of electricity, natural gas, steam and, to a lesser extent, refined fuels by using derivative instruments including futures, forwards, basis swaps, options, transmission congestion contracts and financial transmission rights contracts. Derivatives are recognized on the balance sheet at fair value (see Note L), unless an exception is available under the accounting rules for derivatives and hedging. Qualifying derivative contracts that have been designated as normal purchases or normal sales contracts are not reported at fair value under the accounting rules.

The fair values of the Companies’ commodity derivatives including the offsetting of assets and liabilities on the consolidated balance sheet at March 31, 2015 and December 31, 2014 were:


*(Millions of Dollars)*	2015									2014
Balance Sheet Location	Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)			Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)
Con Edison
Fair value of derivative assets
Current	$	108		$	(23	)	$	85	(b)	$	111		$	(67	)	$	44	(b)
Noncurrent		30			(28	)		2			34			(23	)		11
Total fair value of derivative assets	$	138		$	(51	)	$	87		$	145		$	(90	)	$	55
Fair value of derivative liabilities
Current	$	(174	)	$	137		$	(37	)	$	(242	)	$	139		$	(103	)
Noncurrent		(96	)		72			(24	)		(66	)		91			25
Total fair value of derivative liabilities	$	(270	)	$	209		$	(61	)	$	(308	)	$	230		$	(78	)
Net fair value derivative assets/(liabilities)	$	(132	)	$	158		$	26	(b)	$	(163	)	$	140		$	(23	)(b)
CECONY
Fair value of derivative assets
Current	$	40		$	(29	)	$	11	(b)	$	26		$	(15	)	$	11	(b)
Noncurrent		17			(15	)		2			22			(20	)		2
Total fair value of derivative assets	$	57		$	(44	)	$	13		$	48		$	(35	)	$	13
Fair value of derivative liabilities
Current	$	(69	)	$	46		$	(23	)	$	(96	)	$	48		$	(48	)
Noncurrent		(53	)		37			(16	)		(42	)		32			(10	)
Total fair value of derivative liabilities	$	(122	)	$	83		$	(39	)	$	(138	)	$	80		$	(58	)
Net fair value derivative assets/(liabilities)	$	(65	)	$	39		$	(26	)(b)	$	(90	)	$	45		$	(45	)(b)

(a)

Derivative instruments and collateral were offset on the consolidated balance sheet as applicable under the accounting rules. The Companies enter into master agreements for their commodity derivatives. These agreements typically provide offset in the event of contract termination. In such case, generally the non-defaulting party’s payable will be offset by the defaulting party’s payable. The non-defaulting party will customarily notify the defaulting party within a specific time period and come to an agreement on the early termination amount.

(b)

At March 31, 2015 and December 31, 2014, margin deposits for Con Edison ($37 million and $27 million, respectively) and CECONY ($35 million and $25 million, respectively) were classified as derivative assets in the balance sheet, but not included in the table. Margin is collateral, typically cash, that the holder of a derivative instrument is required to deposit in order to transact on an exchange and to cover its potential losses with its broker or the exchange.

The Utilities generally recover their prudently incurred fuel, purchased power and gas costs, including hedging gains and losses, in accordance with rate provisions approved by the applicable state utility regulators. In accordance with the accounting rules for regulated operations, the Utilities record a regulatory asset or liability to defer recognition of unrealized gains and losses on their electric and gas derivatives. As gains and losses are realized in future periods, they will be recognized as purchased power, gas and fuel costs in the Companies’ consolidated income statements. Con Edison’s competitive energy businesses record realized and unrealized gains and losses on their derivative contracts in purchased power, gas purchased for resale and non-utility revenue in the reporting period in which they occur. Management believes that these derivative instruments represent economic hedges that mitigate exposure to fluctuations in commodity prices.

The following table presents the realized and unrealized gains or losses on commodity derivatives that have been deferred or recognized in earnings for the three months ended March 31, 2015 and 2014:


		Con Edison						CECONY
*(Millions of Dollars)* Balance Sheet Location		2015			2014			2015			2014
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Current	Deferred derivative gains	$	3		$	30		$	3		$	25
Noncurrent	Deferred derivative gains		—			4			—			4
Total deferred gains/(losses)		$	3		$	34		$	3		$	29
Current	Deferred derivative losses	$	43		$	17		$	41		$	17
Current	Recoverable energy costs		—			94			(2	)		77
Noncurrent	Deferred derivative losses		(19	)		2			(16	)		2
Total deferred gains/(losses)		$	24		$	113		$	23		$	96
Net deferred gains/(losses)		$	27		$	147		$	26		$	125
Income Statement Location
Pre-tax gain/(loss) recognized in income
	Purchased power expense	$	21	(a)	$	175	(b)	$	—		$	—
	Gas purchased for resale		(42	)		(14	)		—			—
	Non-utility revenue		42	(a)		(24	)		—			—
Total pre-tax gain/(loss) recognized in income		$	21		$	137		$	—		$	—

(a)	For the three months ended March 31, 2015, Con Edison recorded unrealized gains and losses in non-utility operating revenue ($4 million loss) and purchased power expense ($12 million gain).

(b)	For the three months ended March 31, 2014, Con Edison recorded an unrealized gain of $20 million in purchased power expense.

The following table presents the hedged volume of Con Edison’s and CECONY’s derivative transactions at March 31, 2015:


	Electric Energy (MWHs)(a)(b)		Capacity (MWs)(a)		Natural Gas (Dt)(a)(b)		Refined Fuels (gallons)
Con Edison		19,565,133		6,751		54,964,831		2,352,000
CECONY		6,640,525		2,100		53,860,000		2,352,000

(a)	Volumes are reported net of long and short positions, except natural gas collars where the volumes of long positions are reported.

(b)	Excludes electric congestion and gas basis swap contracts which are associated with electric and gas contracts and hedged volumes.

The Companies are exposed to credit risk related to transactions entered into primarily for the various energy supply and hedging activities by the Utilities and the competitive energy businesses. Credit risk relates to the loss that may result from a counterparty’s nonperformance. The Companies use credit policies to manage this risk, including an established credit approval process, monitoring of counterparty limits, netting provisions within agreements, collateral or prepayment arrangements, credit insurance and credit default swaps. The Companies measure credit risk exposure as the replacement cost for open energy commodity and derivative positions plus amounts owed from counterparties for settled transactions. The replacement cost of open positions represents unrealized gains, net of any unrealized losses where the Companies have a legally enforceable right to offset.

At March 31, 2015, Con Edison and CECONY had $212 million and $35 million of credit exposure in connection with energy supply and hedging activities, net of collateral, respectively. Con Edison’s net credit exposure consisted of $108 million with commodity exchange brokers, $92 million with independent system operators, $8 million with investment-grade counterparties and $4 million with non-investment grade/non-rated counterparties. CECONY’s net credit exposure was with commodity exchange brokers.

The collateral requirements associated with, and settlement of, derivative transactions are included in net cash flows from operating activities in the Companies’ consolidated statement of cash flows. Most derivative instrument contracts contain provisions that may require a party to provide collateral on its derivative instruments that are in a net liability position. The amount of collateral to be provided will depend on the fair value of the derivative instruments and the party’s credit ratings.

The following table presents the aggregate fair value of the Companies’ derivative instruments with credit-risk-related contingent features that are in a net liability position, the collateral posted for such positions and the additional collateral that would have been required to be posted had the lowest applicable credit rating been reduced one level and to below investment grade at March 31, 2015:


*(Millions of Dollars)*	Con Edison (a)			CECONY (a)
Aggregate fair value – net liabilities	$	58		$	40
Collateral posted	$	5		$	—
Additional collateral(b) (downgrade one level from current ratings)	$	—		$	—
Additional collateral(b) (downgrade to below investment grade from current ratings)	$	73	(c)	$	46	(c)

(a)

Non-derivative transactions for the purchase and sale of electricity and gas and qualifying derivative instruments, which have been designated as normal purchases or normal sales, are excluded from the table. These transactions primarily include purchases of electricity from independent system operators. In the event the Utilities and the competitive energy businesses were no longer extended unsecured credit for such purchases, the Companies would be required to post an immaterial amount of collateral at March 31, 2015. For certain other such non-derivative transactions, the Companies could be required to post collateral under certain circumstances, including in the event counterparties had reasonable grounds for insecurity.

(b)

The Companies measure the collateral requirements by taking into consideration the fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liabilities position plus amounts owed to counterparties for settled transactions and amounts required by counterparties for minimum financial security. The fair value amounts represent unrealized losses, net of any unrealized gains where the Companies have a legally enforceable right to offset.

(c)	Derivative instruments that are net assets have been excluded from the table. At March 31, 2015, if Con Edison had been downgraded to below investment grade, it would have been required to post additional collateral for such derivative instruments of $20 million.

CECONY [Member]

Derivative Instruments and Hedging Activities

Note K — Derivative Instruments and Hedging Activities

The fair values of the Companies’ commodity derivatives including the offsetting of assets and liabilities on the consolidated balance sheet at March 31, 2015 and December 31, 2014 were:


*(Millions of Dollars)*	2015									2014
Balance Sheet Location	Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)			Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)
Con Edison
Fair value of derivative assets
Current	$	108		$	(23	)	$	85	(b)	$	111		$	(67	)	$	44	(b)
Noncurrent		30			(28	)		2			34			(23	)		11
Total fair value of derivative assets	$	138		$	(51	)	$	87		$	145		$	(90	)	$	55
Fair value of derivative liabilities
Current	$	(174	)	$	137		$	(37	)	$	(242	)	$	139		$	(103	)
Noncurrent		(96	)		72			(24	)		(66	)		91			25
Total fair value of derivative liabilities	$	(270	)	$	209		$	(61	)	$	(308	)	$	230		$	(78	)
Net fair value derivative assets/(liabilities)	$	(132	)	$	158		$	26	(b)	$	(163	)	$	140		$	(23	)(b)
CECONY
Fair value of derivative assets
Current	$	40		$	(29	)	$	11	(b)	$	26		$	(15	)	$	11	(b)
Noncurrent		17			(15	)		2			22			(20	)		2
Total fair value of derivative assets	$	57		$	(44	)	$	13		$	48		$	(35	)	$	13
Fair value of derivative liabilities
Current	$	(69	)	$	46		$	(23	)	$	(96	)	$	48		$	(48	)
Noncurrent		(53	)		37			(16	)		(42	)		32			(10	)
Total fair value of derivative liabilities	$	(122	)	$	83		$	(39	)	$	(138	)	$	80		$	(58	)
Net fair value derivative assets/(liabilities)	$	(65	)	$	39		$	(26	)(b)	$	(90	)	$	45		$	(45	)(b)

(a)

(b)

The following table presents the realized and unrealized gains or losses on commodity derivatives that have been deferred or recognized in earnings for the three months ended March 31, 2015 and 2014:


		Con Edison						CECONY
*(Millions of Dollars)* Balance Sheet Location		2015			2014			2015			2014
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Current	Deferred derivative gains	$	3		$	30		$	3		$	25
Noncurrent	Deferred derivative gains		—			4			—			4
Total deferred gains/(losses)		$	3		$	34		$	3		$	29
Current	Deferred derivative losses	$	43		$	17		$	41		$	17
Current	Recoverable energy costs		—			94			(2	)		77
Noncurrent	Deferred derivative losses		(19	)		2			(16	)		2
Total deferred gains/(losses)		$	24		$	113		$	23		$	96
Net deferred gains/(losses)		$	27		$	147		$	26		$	125
Income Statement Location
Pre-tax gain/(loss) recognized in income
	Purchased power expense	$	21	(a)	$	175	(b)	$	—		$	—
	Gas purchased for resale		(42	)		(14	)		—			—
	Non-utility revenue		42	(a)		(24	)		—			—
Total pre-tax gain/(loss) recognized in income		$	21		$	137		$	—		$	—

(a)	For the three months ended March 31, 2015, Con Edison recorded unrealized gains and losses in non-utility operating revenue ($4 million loss) and purchased power expense ($12 million gain).

(b)	For the three months ended March 31, 2014, Con Edison recorded an unrealized gain of $20 million in purchased power expense.

The following table presents the hedged volume of Con Edison’s and CECONY’s derivative transactions at March 31, 2015:


	Electric Energy (MWHs)(a)(b)		Capacity (MWs)(a)		Natural Gas (Dt)(a)(b)		Refined Fuels (gallons)
Con Edison		19,565,133		6,751		54,964,831		2,352,000
CECONY		6,640,525		2,100		53,860,000		2,352,000

(a)	Volumes are reported net of long and short positions, except natural gas collars where the volumes of long positions are reported.

(b)	Excludes electric congestion and gas basis swap contracts which are associated with electric and gas contracts and hedged volumes.


*(Millions of Dollars)*	Con Edison (a)			CECONY (a)
Aggregate fair value – net liabilities	$	58		$	40
Collateral posted	$	5		$	—
Additional collateral(b) (downgrade one level from current ratings)	$	—		$	—
Additional collateral(b) (downgrade to below investment grade from current ratings)	$	73	(c)	$	46	(c)

(a)

(b)

(c)	Derivative instruments that are net assets have been excluded from the table. At March 31, 2015, if Con Edison had been downgraded to below investment grade, it would have been required to post additional collateral for such derivative instruments of $20 million.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

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+ Details

Fair Value Measurements

3 Months Ended

Mar. 31, 2015

Fair Value Measurements

Note L — Fair Value Measurements

The accounting rules for fair value measurements and disclosures define fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date in a principal or most advantageous market. Fair value is a market-based measurement that is determined based on inputs, which refer broadly to assumptions that market participants use in pricing assets or liabilities. These inputs can be readily observable, market corroborated, or generally unobservable firm inputs. The Companies often make certain assumptions that market participants would use in pricing the asset or liability, including assumptions about risk, and the risks inherent in the inputs to valuation techniques. The Companies use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs.

The accounting rules for fair value measurements and disclosures established a fair value hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value in three broad levels. The rules require that assets and liabilities be classified in their entirety based on the level of input that is significant to the fair value measurement. Assessing the significance of a particular input may require judgment considering factors specific to the asset or liability, and may affect the valuation of the asset or liability and their placement within the fair value hierarchy. The Companies classify fair value balances based on the fair value hierarchy defined by the accounting rules for fair value measurements and disclosures as follows:

•

Level 1 – Consists of assets or liabilities whose value is based on unadjusted quoted prices in active markets at the measurement date. An active market is one in which transactions for assets or liabilities occur with sufficient frequency and volume to provide pricing information on an ongoing basis. This category includes contracts traded on active exchange markets valued using unadjusted prices quoted directly from the exchange.

•

Level 2 – Consists of assets or liabilities valued using industry standard models and based on prices, other than quoted prices within Level 1, that are either directly or indirectly observable as of the measurement date. The industry standard models consider observable assumptions including time value, volatility factors and current market and contractual prices for the underlying commodities, in addition to other economic measures. This category includes contracts traded on active exchanges or in over-the-counter markets priced with industry standard models.

•

Level 3 – Consists of assets or liabilities whose fair value is estimated based on internally developed models or methodologies using inputs that are generally less readily observable and supported by little, if any, market activity at the measurement date. Unobservable inputs are developed based on the best available information and subject to cost benefit constraints. This category includes contracts priced using models that are internally developed and contracts placed in illiquid markets. It also includes contracts that expire after the period of time for which quoted prices are available and internal models are used to determine a significant portion of the value.

Assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 are summarized below.


	2015											2014
*(Millions of Dollars)*	Level 1		Level 2		Level 3		Netting Adjustment (e)			Total		Level 1		Level 2		Level 3		Netting Adjustment (e)			Total
Con Edison
Derivative assets:
Commodity(a)(b)(c)	$	1	$	62	$	17	$	44		$	124	$	3	$	78	$	28	$	(27	)	$	82
Other(a)(b)(d)		167		120		—		—			287		163		116		—		—			279
Total assets	$	168	$	182	$	17	$	44		$	411	$	166	$	194	$	28	$	(27	)	$	361
Derivative liabilities:
Commodity(a)(b)(c)	$	14	$	193	$	6	$	(151	)	$	62	$	18	$	246	$	8	$	(194	)	$	78
CECONY
Derivative assets
Commodity(a)(b)(c)	$	1	$	9	$	12	$	26		$	48	$	1	$	3	$	13	$	21		$	38
Other(a)(b)(d)		159		110		—		—			269		155		106		—		—			261
Total assets	$	160	$	119	$	12	$	26		$	317	$	156	$	109	$	13	$	21		$	299
Derivative liabilities:
Commodity(a)(b)(c)	$	12	$	75	$	—	$	(48	)	$	39	$	16	$	91	$	—	$	(49	)	$	58

(a)	The Companies’ policy is to review the fair value hierarchy and recognize transfers into and transfers out of the levels at the end of each reporting period. There were no transfers between levels 1, 2 and 3 for the three months ended March 31, 2015 and for the year ended December 31, 2014.

(b)

Level 2 assets and liabilities include investments held in the deferred compensation plan and/or non-qualified retirement plans, exchange-traded contracts where there is insufficient market liquidity to warrant inclusion in Level 1, certain over-the-counter derivative instruments for electricity, refined products and natural gas. Derivative instruments classified as Level 2 are valued using industry standard models that incorporate corroborated observable inputs; such as pricing services or prices from similar instruments that trade in liquid markets, time value and volatility factors.

(c)

The accounting rules for fair value measurements and disclosures require consideration of the impact of nonperformance risk (including credit risk) from a market participant perspective in the measurement of the fair value of assets and liabilities. At March 31, 2015 and December 31, 2014, the Companies determined that nonperformance risk would have no material impact on their financial position or results of operations.

(d)	Other assets are comprised of assets such as life insurance contracts within the deferred compensation plan and non-qualified retirement plans.

(e)	Amounts represent the impact of legally-enforceable master netting agreements that allow the Companies to net gain and loss positions and cash collateral held or placed with the same counterparties.

The employees in the Companies’ risk management group develop and maintain the Companies’ valuation policies and procedures for, and verify pricing and fair value valuation of, commodity derivatives. Under the Companies’ policies and procedures, multiple independent sources of information are obtained for forward price curves used to value commodity derivatives. Fair value and changes in fair value of commodity derivatives are reported on a monthly basis to the Companies’ risk committees, comprised of officers and employees of the Companies that oversee energy hedging at the Utilities and the competitive energy businesses. The risk management group reports to the Companies’ Vice President and Treasurer.


	Fair Value of Level 3 at March 31, 2015 *(Millions of Dollars)*		Valuation Techniques	Unobservable Inputs	Range
Con Edison – Commodity
Electricity		$ (3)	Discounted Cash Flow	Forward energy prices (a)	$24.50-$121.00 per MWH
			Discounted Cash Flow	Forward capacity prices (a)	$0.75-$8.45 per kW-month
Transmission Congestion Contracts/Financial Transmission Rights		14	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%
				Inter-zonal forward price curves adjusted for historical zonal losses (b)	$(2.65)-$9.48 per MWH
Total Con Edison—Commodity		$ 11
CECONY—Commodity
Transmission Congestion Contracts		$ 12	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%

(a)	Generally, increases/(decreases) in this input in isolation would result in a higher/(lower) fair value measurement.

(b)	Generally, increases/(decreases) in this input in isolation would result in a lower/(higher) fair value measurement.

The table listed below provides a reconciliation of the beginning and ending net balances for assets and liabilities measured at fair value as of March 31, 2015 and 2014 and classified as Level 3 in the fair value hierarchy:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance as of January 1,	$	20		$	9		$	13		$	6
Included in earnings		(10	)		50			(2	)		11
Included in regulatory assets and liabilities		—			4			—			4
Purchases		3			8			2			7
Settlements		(2	)		(47	)		(1	)		(15	)
Ending balance as of March 31,	$	11		$	24		$	12		$	13

For the Utilities, realized gains and losses on Level 3 commodity derivative assets and liabilities are reported as part of purchased power, gas and fuel costs. The Utilities generally recover these costs in accordance with rate provisions approved by the applicable state public utilities regulators. Unrealized gains and losses for commodity derivatives are generally deferred on the consolidated balance sheet in accordance with the accounting rules for regulated operations.

For the competitive energy businesses, realized and unrealized gains and losses on Level 3 commodity derivative assets and liabilities are reported in non-utility revenues (immaterial for both periods) and purchased power costs ($8 million loss and $39 million gain) on the consolidated income statement for the three months ended March 31, 2015 and 2014, respectively. The change in fair value relating to Level 3 commodity derivative assets and liabilities held at March 31, 2015 and 2014 is included in non-utility revenues (immaterial for both periods) and purchased power costs ($5 million loss and $8 million gain) on the consolidated income statement for the three months ended March 31, 2015 and 2014, respectively.

CECONY [Member]

Fair Value Measurements

Note L — Fair Value Measurements

•

Assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 are summarized below.


	2015											2014
*(Millions of Dollars)*	Level 1		Level 2		Level 3		Netting Adjustment (e)			Total		Level 1		Level 2		Level 3		Netting Adjustment (e)			Total
Con Edison
Derivative assets:
Commodity(a)(b)(c)	$	1	$	62	$	17	$	44		$	124	$	3	$	78	$	28	$	(27	)	$	82
Other(a)(b)(d)		167		120		—		—			287		163		116		—		—			279
Total assets	$	168	$	182	$	17	$	44		$	411	$	166	$	194	$	28	$	(27	)	$	361
Derivative liabilities:
Commodity(a)(b)(c)	$	14	$	193	$	6	$	(151	)	$	62	$	18	$	246	$	8	$	(194	)	$	78
CECONY
Derivative assets
Commodity(a)(b)(c)	$	1	$	9	$	12	$	26		$	48	$	1	$	3	$	13	$	21		$	38
Other(a)(b)(d)		159		110		—		—			269		155		106		—		—			261
Total assets	$	160	$	119	$	12	$	26		$	317	$	156	$	109	$	13	$	21		$	299
Derivative liabilities:
Commodity(a)(b)(c)	$	12	$	75	$	—	$	(48	)	$	39	$	16	$	91	$	—	$	(49	)	$	58

(a)	The Companies’ policy is to review the fair value hierarchy and recognize transfers into and transfers out of the levels at the end of each reporting period. There were no transfers between levels 1, 2 and 3 for the three months ended March 31, 2015 and for the year ended December 31, 2014.

(b)

(c)

(d)	Other assets are comprised of assets such as life insurance contracts within the deferred compensation plan and non-qualified retirement plans.

(e)	Amounts represent the impact of legally-enforceable master netting agreements that allow the Companies to net gain and loss positions and cash collateral held or placed with the same counterparties.


	Fair Value of Level 3 at March 31, 2015 *(Millions of Dollars)*		Valuation Techniques	Unobservable Inputs	Range
Con Edison – Commodity
Electricity		$ (3)	Discounted Cash Flow	Forward energy prices (a)	$24.50-$121.00 per MWH
			Discounted Cash Flow	Forward capacity prices (a)	$0.75-$8.45 per kW-month
Transmission Congestion Contracts/Financial Transmission Rights		14	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%
				Inter-zonal forward price curves adjusted for historical zonal losses (b)	$(2.65)-$9.48 per MWH
Total Con Edison—Commodity		$ 11
CECONY—Commodity
Transmission Congestion Contracts		$ 12	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%

(a)	Generally, increases/(decreases) in this input in isolation would result in a higher/(lower) fair value measurement.

(b)	Generally, increases/(decreases) in this input in isolation would result in a lower/(higher) fair value measurement.


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance as of January 1,	$	20		$	9		$	13		$	6
Included in earnings		(10	)		50			(2	)		11
Included in regulatory assets and liabilities		—			4			—			4
Purchases		3			8			2			7
Settlements		(2	)		(47	)		(1	)		(15	)
Ending balance as of March 31,	$	11		$	24		$	12		$	13

Variable Interest Entities

3 Months Ended

Mar. 31, 2015

Variable Interest Entities

Note M — Variable Interest Entities

Con Edison enters into arrangements including leases, partnerships and electricity purchase agreements, with various entities. As a result of these arrangements, Con Edison retains or may retain a variable interest in these entities.

CECONY has a variable interest in a non-consolidated variable interest entity (VIE), Astoria Energy, LLC (Astoria Energy), with which CECONY has entered into a long-term electricity purchase agreement. CECONY is not the primary beneficiary of this VIE since CECONY does not have the power to direct activities that CECONY believes most significantly impact the economic performance of Astoria Energy. In particular, CECONY has not invested in, or guaranteed the indebtedness of, Astoria Energy and CECONY does not operate or maintain Astoria Energy’s generating facilities. CECONY also has long-term electricity purchase agreements with the following three potential VIEs: Cogen Technologies Linden Venture, LP, Brooklyn Navy Yard Cogeneration Partners, LP and Indeck Energy Services of Corinth, Inc. In 2014, requests were made of these three counterparties for information necessary to determine whether the entity was a VIE and whether CECONY is the primary beneficiary; however, the information was not made available. The payments pursuant to these agreements, which constitute CECONY’s maximum exposure to loss with respect to the potential VIEs, for the first quarter of 2015 were $105 million for Cogen Technologies Linden Venture, LP, $30 million for Brooklyn Navy Yard Cogeneration Partners, LP and $15 million for Indeck Energy Services of Corinth, Inc.

During the first quarter of 2015, there were no new investments entered into that qualified for VIE status. The following table summarizes the VIEs in which Con Edison Development has entered into as of March 31, 2015:


Project Name (a)	Generating Capacity Owned (MWs AC)		Power Purchase Agreement Term in Years			Year of Initial Investment		Location		Maximum Exposure to Loss (Millions of Dollars)(c)
Pilesgrove		9		n/a	(b)		2010		New Jersey		$26
Mesquite Solar 1		83		20			2013		Arizona		100
Copper Mountain Solar 2		75		25			2013		Nevada		79
Copper Mountain Solar 3		128		20			2014		Nevada		187
California Solar		55		25			2012		California		71
Texas Solar 4		32		25			2014		Texas		55
Broken Bow II		37		25			2014		Nebraska		57

(a)

With the exception of Texas Solar 4, Con Edison’s ownership interest is 50 percent and these projects are accounted for using the equity method of accounting. Con Edison is not the primary beneficiary since the power to direct the activities that most significantly impact the economics of the entities are shared equally between Con Edison Development and third parties. Con Edison’s ownership interest in Texas Solar 4 is 80 percent and is consolidated in the financial statements. Con Edison is the primary beneficiary since the power to direct the activities that most significantly impact the economics of Texas Solar 4 is held by Con Edison Development. The maximum exposure for Texas Solar 4 is the net assets of the investment offset by a $9 million noncontrolling interest.

(b)	Pilesgrove has 3-5 year Solar Renewable Energy Credit hedges in place.

(c)

For investments accounted for under the equity method, maximum exposure is equal to the carrying value of the investment on the balance sheet. For consolidated investments, maximum exposure is equal to the net assets of the investment on the balance sheet less any applicable minority interest. Con Edison did not provide any financial or other support during the year that was not previously contractually required.

CECONY [Member]

Variable Interest Entities

Note M — Variable Interest Entities


Project Name (a)	Generating Capacity Owned (MWs AC)		Power Purchase Agreement Term in Years			Year of Initial Investment		Location		Maximum Exposure to Loss (Millions of Dollars)(c)
Pilesgrove		9		n/a	(b)		2010		New Jersey		$26
Mesquite Solar 1		83		20			2013		Arizona		100
Copper Mountain Solar 2		75		25			2013		Nevada		79
Copper Mountain Solar 3		128		20			2014		Nevada		187
California Solar		55		25			2012		California		71
Texas Solar 4		32		25			2014		Texas		55
Broken Bow II		37		25			2014		Nebraska		57

(a)

(b)	Pilesgrove has 3-5 year Solar Renewable Energy Credit hedges in place.

(c)

New Financial Accounting Standards	3 Months Ended
New Financial Accounting Standards	Mar. 31, 2015
New Financial Accounting Standards	Note N — New Financial Accounting Standards In January 2015, the Financial Accounting Standards Board (FASB) issued amendments on income statement guidance through Accounting Standards Update (ASU) No. 2015-01, “Income Statement—Extraordinary and Unusual Items (Subtopic 225-20).” The amendments reduce the complexity of accounting standards related to the income statement by eliminating the requirement to report extraordinary items separately. The amendments are effective for reporting periods beginning on or after December 15, 2015. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The application of this guidance is not expected to have a material impact on the Companies’ financial position, results of operations and liquidity. In February 2015, the FASB issued amendments on consolidation guidance through ASU No. 2015-02, “Consolidation (Topic 810).” The amendments provide additional guidance for VIE accounting of limited partnerships and similar legal entities, fees paid to decision makers of a VIE, the effect of fee arrangements on primary beneficiary determination, the effect of related parties on primary beneficiary determination. For public entities, the amendments are effective prospectively for reporting periods beginning on or after December 15, 2015. Early adoption is permitted. The Companies are evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity. In April 2015, the FASB issued amendments on debt issuance costs guidance through ASU No. 2015-03, “Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs.” The amendments provide additional guidance requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability rather than as a deferred cost (i.e. an asset) as required by current guidance. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity. In April 2015, the FASB issued amendments on internal-use software guidance through ASU No. 2015-05, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement.” The amendments provide guidance to customers about whether a cloud computing arrangement would be accounted for as a license of internal use software. If the arrangement is not deemed to contain a software license, it would be accounted for as a service contract. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity.
CECONY [Member]
New Financial Accounting Standards	Note N — New Financial Accounting Standards In January 2015, the Financial Accounting Standards Board (FASB) issued amendments on income statement guidance through Accounting Standards Update (ASU) No. 2015-01, “Income Statement—Extraordinary and Unusual Items (Subtopic 225-20).” The amendments reduce the complexity of accounting standards related to the income statement by eliminating the requirement to report extraordinary items separately. The amendments are effective for reporting periods beginning on or after December 15, 2015. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The application of this guidance is not expected to have a material impact on the Companies’ financial position, results of operations and liquidity. In February 2015, the FASB issued amendments on consolidation guidance through ASU No. 2015-02, “Consolidation (Topic 810).” The amendments provide additional guidance for VIE accounting of limited partnerships and similar legal entities, fees paid to decision makers of a VIE, the effect of fee arrangements on primary beneficiary determination, the effect of related parties on primary beneficiary determination. For public entities, the amendments are effective prospectively for reporting periods beginning on or after December 15, 2015. Early adoption is permitted. The Companies are evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity. In April 2015, the FASB issued amendments on debt issuance costs guidance through ASU No. 2015-03, “Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs.” The amendments provide additional guidance requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability rather than as a deferred cost (i.e. an asset) as required by current guidance. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity. In April 2015, the FASB issued amendments on internal-use software guidance through ASU No. 2015-05, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement.” The amendments provide guidance to customers about whether a cloud computing arrangement would be accounted for as a license of internal use software. If the arrangement is not deemed to contain a software license, it would be accounted for as a service contract. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity.

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2015

Accounting Policies [Abstract]

Earnings Per Common Share

Earnings Per Common Share

For the three months ended March 31, 2015 and 2014, basic and diluted earnings per share (EPS) for Con Edison are calculated as follows:


*(Millions of Dollars, except per share amounts/Shares in Millions)*	2015		2014
Net income for common stock		$370		$361
Weighted average common shares outstanding – basic		292.9		292.9
Add: Incremental shares attributable to effect of potentially dilutive securities		1.0		1.2
Adjusted weighted average common shares outstanding – diluted		293.9		294.1
Net Income for common stock per common share – basic		$1.26		$1.23
Net Income for common stock per common share – diluted		$1.26		$1.23

The computation of diluted EPS for the three months ended March 31, 2015 and 2014 exclude immaterial amounts of performance share awards that were not included because of their anti-dilutive effect.

Changes in Accumulated Other Comprehensive Income/Loss by Component

Changes in Accumulated Other Comprehensive Income/(Loss) by Component

For the three months ended March 31, 2015 and 2014, changes to accumulated other comprehensive income/(loss) (OCI) for Con Edison and CECONY are as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance, accumulated OCI, net of taxes (b)		$(45	)		$(25	)		$(11	)		$(6	)
OCI before reclassifications, net of tax of $(2) and $(1) in 2015 and 2014, respectively, for Con Edison		3			2			—			—
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax of $(1) and $(1) in 2015 and 2014, respectively, for Con Edison (a)(b)		2			2			—			1
Current Period OCI, net of taxes		5			4			—			1
Ending balance, accumulated OCI, net of taxes		$(40	)		$(21	)		$(11	)		$(5	)

(a)

(b)	Tax reclassified from accumulated OCI is reported in the income tax expense line item of the income statement.

New Financial Accounting Standards

New Financial Accounting Standards

In January 2015, the Financial Accounting Standards Board (FASB) issued amendments on income statement guidance through Accounting Standards Update (ASU) No. 2015-01, “Income Statement—Extraordinary and Unusual Items (Subtopic 225-20).” The amendments reduce the complexity of accounting standards related to the income statement by eliminating the requirement to report extraordinary items separately. The amendments are effective for reporting periods beginning on or after December 15, 2015. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The application of this guidance is not expected to have a material impact on the Companies’ financial position, results of operations and liquidity.

In February 2015, the FASB issued amendments on consolidation guidance through ASU No. 2015-02, “Consolidation (Topic 810).” The amendments provide additional guidance for VIE accounting of limited partnerships and similar legal entities, fees paid to decision makers of a VIE, the effect of fee arrangements on primary beneficiary determination, the effect of related parties on primary beneficiary determination. For public entities, the amendments are effective prospectively for reporting periods beginning on or after December 15, 2015. Early adoption is permitted. The Companies are evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity.

In April 2015, the FASB issued amendments on debt issuance costs guidance through ASU No. 2015-03, “Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs.” The amendments provide additional guidance requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability rather than as a deferred cost (i.e. an asset) as required by current guidance. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity.

In April 2015, the FASB issued amendments on internal-use software guidance through ASU No. 2015-05, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement.” The amendments provide guidance to customers about whether a cloud computing arrangement would be accounted for as a license of internal use software. If the arrangement is not deemed to contain a software license, it would be accounted for as a service contract. For public entities, the amendments are effective for reporting periods beginning after December 15, 2015. Early adoption is permitted. The Companies are in the process of evaluating the application and impact of the new guidance on the Companies’ financial position, results of operations and liquidity.

- Definition

Disclosure of accounting policy for computing basic and diluted earnings or loss per share for each class of common stock and participating security. Addresses all significant policy factors, including any antidilutive items that have been excluded from the computation and takes into account stock dividends, splits and reverse splits that occur after the balance sheet date of the latest reporting period but before the issuance of the financial statements.

+ References+ Details

Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2015

Accounting Policies [Abstract]

Earnings Per Common Share

For the three months ended March 31, 2015 and 2014, basic and diluted earnings per share (EPS) for Con Edison are calculated as follows:


*(Millions of Dollars, except per share amounts/Shares in Millions)*	2015		2014
Net income for common stock		$370		$361
Weighted average common shares outstanding – basic		292.9		292.9
Add: Incremental shares attributable to effect of potentially dilutive securities		1.0		1.2
Adjusted weighted average common shares outstanding – diluted		293.9		294.1
Net Income for common stock per common share – basic		$1.26		$1.23
Net Income for common stock per common share – diluted		$1.26		$1.23

Changes in Accumulated Other Comprehensive Income/(Loss) by Component

For the three months ended March 31, 2015 and 2014, changes to accumulated other comprehensive income/(loss) (OCI) for Con Edison and CECONY are as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance, accumulated OCI, net of taxes (b)		$(45	)		$(25	)		$(11	)		$(6	)
OCI before reclassifications, net of tax of $(2) and $(1) in 2015 and 2014, respectively, for Con Edison		3			2			—			—
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax of $(1) and $(1) in 2015 and 2014, respectively, for Con Edison (a)(b)		2			2			—			1
Current Period OCI, net of taxes		5			4			—			1
Ending balance, accumulated OCI, net of taxes		$(40	)		$(21	)		$(11	)		$(5	)

(a)

(b)	Tax reclassified from accumulated OCI is reported in the income tax expense line item of the income statement.

- Definition

Tabular disclosure of the effect of income (loss) on an entity's diluted earnings per share.

+ References+ Details

Regulatory Matters (Tables)

3 Months Ended

Mar. 31, 2015

Regulatory Assets and Liabilities

Regulatory assets and liabilities at March 31, 2015 and December 31, 2014 were comprised of the following items:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Regulatory assets
Unrecognized pension and other postretirement costs	$	4,593	$	4,846	$	4,374	$	4,609
Future income tax		2,289		2,273		2,180		2,166
Environmental remediation costs		911		925		808		820
Deferred storm costs		287		319		196		224
Revenue taxes		223		219		211		208
Surcharge for New York State assessment		96		99		90		92
Pension and other postretirement benefits deferrals		61		66		35		42
Net electric deferrals		58		63		58		63
Unamortized loss on reacquired debt		56		57		53		55
Deferred derivative losses – noncurrent		44		25		40		23
Recoverable energy costs – noncurrent		42		19		42		17
O&R property tax reconciliation		40		36		—		—
O&R transition bond charges		25		27		—		—
Preferred stock redemption		27		27		27		27
Workers’ compensation		9		8		9		8
Other		145		147		128		127
Regulatory assets – noncurrent		8,906		9,156		8,251		8,481
Deferred derivative losses – current		55		97		51		92
Future income tax – current		10		10		—		—
Recoverable energy costs – current		1		41		—		40
Regulatory assets – current		66		148		51		132
Total Regulatory Assets	$	8,972	$	9,304	$	8,302	$	8,613
Regulatory liabilities
Allowance for cost of removal less salvage	$	614	$	598	$	514	$	499
Property tax reconciliation		297		295		297		295
Base rate change deferrals		153		155		153		155
Prudence proceeding		104		105		104		105
Pension and other postretirement benefit deferrals		85		46		64		37
Property tax refunds		76		87		76		87
Variable-rate tax-exempt debt – cost rate reconciliation		74		78		74		78
Net unbilled revenue deferrals		71		138		71		138
New York State income tax rate change		63		62		60		59
Carrying charges on repair allowance and bonus depreciation		52		58		50		57
World Trade Center settlement proceeds		36		41		36		41
Net utility plant reconciliations		21		21		21		20
Earnings sharing – electric		19		19		18		18
Unrecognized other postretirement costs		15		—		13		—
Other		212		290		177		248
Regulatory liabilities – noncurrent		1,892		1,993		1,728		1,837
Refundable energy costs – current		177		128		152		84
Revenue decoupling mechanism		30		30		30		30
Future income tax		25		24		24		24
Deferred derivative gains – current		8		5		6		4
Regulatory liabilities – current		240		187		212		142
Total Regulatory Liabilities	$	2,132	$	2,180	$	1,940	$	1,979

Electric [Member] | CECONY [Member]

Summary of Rate Plan

The following table contains a summary of the rate plan for 2016:


Effective period		January 2016 – December 2016
Base rate changes		None (a)
Amortizations to income of net regulatory (assets) liabilities		Additional $123 million of net regulatory liabilities (b)
Other revenue sources		Continued retention of $90 million of annual transmission congestion revenues
Revenue decoupling mechanism		Continued reconciliation of actual electric delivery revenues to those authorized in the rate plan
Recoverable energy costs		Continued current rate recovery of purchased power and fuel costs
Negative revenue adjustments		Continued potential for penalties of up to $400 million if certain performance targets are not met
Cost reconciliations		Continued reconciliation of expenses for pension and other postretirement benefits, variable-rate tax-exempt debt, major storms, property taxes (c), municipal infrastructure support, the impact of new laws and environmental remediation to amounts reflected in rates
Net utility plant reconciliations		Target levels reflected in rates are as follows: Transmission and distribution: $17,929 million Storm hardening: $268 million Other: $2,069 million
Average rate base		$18,282 million
Weighted average cost of capital (after-tax)		6.91 percent
Authorized return on common equity		9.0 percent
Earnings sharing		Most earnings above an annual earnings threshold of 9.6 percent are to be applied to reduce regulatory assets for environmental remediation and other costs
Cost of long-term debt		5.09 percent
Common equity ratio		48 percent

(a)

(b)

(c)	Deferrals for property taxes will continue to be limited to 90 percent of the difference from amounts reflected in rates, subject to an annual maximum for the remaining difference of not more than a 10 basis point impact on return on common equity.

Capitalization (Tables)

3 Months Ended

Mar. 31, 2015

Text Block [Abstract]

Carrying Amounts and Fair Values of Long-Term Debt

The carrying amounts and fair values of long-term debt at March 31, 2015 and December 31, 2014 are:


*(Millions of Dollars)*	2015				2014
Long-Term Debt (including current portion)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Con Edison		$12,190		$14,224		$12,191		$13,998
CECONY		$11,214		$13,066		$11,214		$12,846

Pension Benefits (Tables)

3 Months Ended

Mar. 31, 2015

Pension Benefits [Member]

Total Periodic Benefit Costs

The components of the Companies’ total periodic benefit costs for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Service cost – including administrative expenses	$	74		$	57		$	70		$	53
Interest cost on projected benefit obligation		144			143			135			134
Expected return on plan assets		(222	)		(208	)		(210	)		(197	)
Recognition of net actuarial loss		194			154			183			146
Recognition of prior service costs		1			1			—			1
TOTAL PERIODIC BENEFIT COST	$	191		$	147		$	178		$	137
Cost capitalized		(68	)		(51	)		(65	)		(49	)
Reconciliation to rate level		(24	)		26			(24	)		23
Cost charged to operating expenses	$	99		$	122		$	89		$	111

Other Postretirement Benefits [Member]

Total Periodic Benefit Costs

The components of the Companies’ total periodic other postretirement benefit costs for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Service cost	$	5		$	5		$	4		$	4
Interest cost on accumulated other postretirement benefit obligation		13			15			11			13
Expected return on plan assets		(20	)		(19	)		(17	)		(17	)
Recognition of net actuarial loss		8			14			7			13
Recognition of prior service cost		(5	)		(5	)		(4	)		(4	)
TOTAL PERIODIC OTHER POSTRETIREMENT BENEFIT COST	$	1		$	10		$	1		$	9
Cost capitalized		(1	)		(4	)		(1	)		(3	)
Reconciliation to rate level		4			3			2			—
Cost charged to operating expenses	$	4		$	9		$	2		$	6

Environmental Matters (Tables)

3 Months Ended

Mar. 31, 2015

Environmental Remediation Obligations [Abstract]

Accrued Liabilities and Regulatory Assets

The accrued liabilities and regulatory assets related to Superfund Sites at March 31, 2015 and December 31, 2014 were as follows:


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued Liabilities:
Manufactured gas plant sites		$678		$684		$582		$587
Other Superfund Sites		80		80		80		79
Total		$758		$764		$662		$666
Regulatory assets		$911		$925		$808		$820

Environmental Remediation Costs

Environmental remediation costs incurred and insurance recoveries received related to Superfund Sites for the three months ended March 31, 2015 and 2014 were as follows:


	Con Edison				CECONY
(Millions of Dollars)	2015		2014		2015		2014
Remediation costs incurred		$7		$9		$6		$8
Insurance recoveries received*		—		5		—		5
* Reduced amount deferred for recovery from customers

Accrued Liability for Asbestos Suits and Workers' Compensation Proceedings


	Con Edison				CECONY
*(Millions of Dollars)*	2015		2014		2015		2014
Accrued liability – asbestos suits	$	8	$	8	$	7	$	7
Regulatory assets – asbestos suits	$	8	$	8	$	7	$	7
Accrued liability – workers’ compensation	$	84	$	83	$	79	$	78
Regulatory assets – workers’ compensation	$	9	$	8	$	9	$	8

Other Material Contingencies (Tables)

3 Months Ended

Mar. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Total Guarantees

A summary, by type and term, of Con Edison’s total guarantees at March 31, 2015 is as follows:


Guarantee Type	0 – 3 years		4 – 10 years		> 10 years		Total
	*(Millions of Dollars)*
NY Transco		$1,360		$—		$—		$1,360
Energy transactions		830		38		90		958
Renewable electric production projects		204		—		7		211
Other		30		—		—		30
Total		$2,424		$38		$97		$2,559

Financial Information by Business Segment (Tables)

3 Months Ended

Mar. 31, 2015

Segment Reporting [Abstract]

Financial Data for Business Segments

The financial data for the business segments are as follows:


	For the Three Months Ended March 31,
	Operating revenues					Inter-segment revenues						Depreciation and amortization				Operating income
	2015			2014		2015			2014			2015		2014		2015			2014
CECONY
Electric	$	1,980		$	2,074	$	4		$	4		$	202	$	189	$	279		$	257
Gas		655			789		1			1			35		32		241			233
Steam		375			341		22			20			20		19		164			153
Consolidation adjustments		—			—		(27	)		(25	)		—		—		—			—
Total CECONY	$	3,010		$	3,204	$	—		$	—		$	257	$	240	$	684		$	643
O&R
Electric	$	156		$	163	$	—		$	—		$	12	$	10	$	18		$	12
Gas		77			93		—			—			5		4		27			27
Total O&R	$	233		$	256	$	—		$	—		$	17	$	14	$	45		$	39
Competitive energy businesses	$	374		$	329	$	(3	)	$	3		$	5		7	$	(3	)	$	2
Other(a)		(1	)		—		3			(3	)		—		—		—			1
Total Con Edison	$	3,616		$	3,789	$	—		$	—		$	279	$	261	$	726		$	685

(a)	Parent company and consolidation adjustments. Other does not represent a business segment.

- Definition

Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

+ References+ Details

Derivative Instruments and Hedging Activities (Tables)

3 Months Ended

Mar. 31, 2015

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair Values of Commodity Derivatives Including Offsetting of Assets and Liabilities

The fair values of the Companies’ commodity derivatives including the offsetting of assets and liabilities on the consolidated balance sheet at March 31, 2015 and December 31, 2014 were:


*(Millions of Dollars)*	2015									2014
Balance Sheet Location	Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)			Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset			Net Amounts of Assets/ (Liabilities)(a)
Con Edison
Fair value of derivative assets
Current	$	108		$	(23	)	$	85	(b)	$	111		$	(67	)	$	44	(b)
Noncurrent		30			(28	)		2			34			(23	)		11
Total fair value of derivative assets	$	138		$	(51	)	$	87		$	145		$	(90	)	$	55
Fair value of derivative liabilities
Current	$	(174	)	$	137		$	(37	)	$	(242	)	$	139		$	(103	)
Noncurrent		(96	)		72			(24	)		(66	)		91			25
Total fair value of derivative liabilities	$	(270	)	$	209		$	(61	)	$	(308	)	$	230		$	(78	)
Net fair value derivative assets/(liabilities)	$	(132	)	$	158		$	26	(b)	$	(163	)	$	140		$	(23	)(b)
CECONY
Fair value of derivative assets
Current	$	40		$	(29	)	$	11	(b)	$	26		$	(15	)	$	11	(b)
Noncurrent		17			(15	)		2			22			(20	)		2
Total fair value of derivative assets	$	57		$	(44	)	$	13		$	48		$	(35	)	$	13
Fair value of derivative liabilities
Current	$	(69	)	$	46		$	(23	)	$	(96	)	$	48		$	(48	)
Noncurrent		(53	)		37			(16	)		(42	)		32			(10	)
Total fair value of derivative liabilities	$	(122	)	$	83		$	(39	)	$	(138	)	$	80		$	(58	)
Net fair value derivative assets/(liabilities)	$	(65	)	$	39		$	(26	)(b)	$	(90	)	$	45		$	(45	)(b)

(a)

(b)

Realized and Unrealized Gains or Losses on Commodity Derivatives

The following table presents the realized and unrealized gains or losses on commodity derivatives that have been deferred or recognized in earnings for the three months ended March 31, 2015 and 2014:


		Con Edison						CECONY
*(Millions of Dollars)* Balance Sheet Location		2015			2014			2015			2014
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Current	Deferred derivative gains	$	3		$	30		$	3		$	25
Noncurrent	Deferred derivative gains		—			4			—			4
Total deferred gains/(losses)		$	3		$	34		$	3		$	29
Current	Deferred derivative losses	$	43		$	17		$	41		$	17
Current	Recoverable energy costs		—			94			(2	)		77
Noncurrent	Deferred derivative losses		(19	)		2			(16	)		2
Total deferred gains/(losses)		$	24		$	113		$	23		$	96
Net deferred gains/(losses)		$	27		$	147		$	26		$	125
Income Statement Location
Pre-tax gain/(loss) recognized in income
	Purchased power expense	$	21	(a)	$	175	(b)	$	—		$	—
	Gas purchased for resale		(42	)		(14	)		—			—
	Non-utility revenue		42	(a)		(24	)		—			—
Total pre-tax gain/(loss) recognized in income		$	21		$	137		$	—		$	—

(a)	For the three months ended March 31, 2015, Con Edison recorded unrealized gains and losses in non-utility operating revenue ($4 million loss) and purchased power expense ($12 million gain).

(b)	For the three months ended March 31, 2014, Con Edison recorded an unrealized gain of $20 million in purchased power expense.

Hedged Volume of Derivative Transactions

The following table presents the hedged volume of Con Edison’s and CECONY’s derivative transactions at March 31, 2015:


	Electric Energy (MWHs)(a)(b)		Capacity (MWs)(a)		Natural Gas (Dt)(a)(b)		Refined Fuels (gallons)
Con Edison		19,565,133		6,751		54,964,831		2,352,000
CECONY		6,640,525		2,100		53,860,000		2,352,000

(a)	Volumes are reported net of long and short positions, except natural gas collars where the volumes of long positions are reported.

(b)	Excludes electric congestion and gas basis swap contracts which are associated with electric and gas contracts and hedged volumes.

Aggregate Fair Value of Companies' Derivative Instruments with Credit-Risk-Related Contingent Features


*(Millions of Dollars)*	Con Edison (a)			CECONY (a)
Aggregate fair value – net liabilities	$	58		$	40
Collateral posted	$	5		$	—
Additional collateral(b) (downgrade one level from current ratings)	$	—		$	—
Additional collateral(b) (downgrade to below investment grade from current ratings)	$	73	(c)	$	46	(c)

(a)

(b)

(c)	Derivative instruments that are net assets have been excluded from the table. At March 31, 2015, if Con Edison had been downgraded to below investment grade, it would have been required to post additional collateral for such derivative instruments of $20 million.

- Definition

Tabular disclosure of credit derivatives which includes information by sellers of credit derivatives, about each credit derivative, or each group of similar credit derivatives, including (a) the nature of the credit derivative - its term, how it arose, the events or circumstances that would require the seller to perform under the credit derivative, and the current status of the payment/performance risk of the credit derivative; (b) the maximum potential amount of future payments (undiscounted) the seller could be required to make under the credit derivative; (c) the current fair value of the credit derivative; and (d) the nature of any recourse provisions under the credit derivative, and any assets held either as collateral or by third parties. A credit derivative is a derivative instrument (1) in which one or more of its underlyings are related to the credit risk of a specified entity (or a group of entities) or an index based on the credit risk of a group of entities and (2) that exposes the seller to potential loss from credit-risk-related events specified in the contract. Examples of credit derivatives within the scope of this paragraph include, but are not limited to, credit default swaps, credit spread options, and credit index products; also includes a hybrid instrument that has an embedded credit derivative (for example, but not limited to, a credit-linked note).

+ References+ Details

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Paragraph 1

-Subparagraph (SX 210.4-08.(n)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2015

Fair Value Disclosures [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 are summarized below.


	2015											2014
*(Millions of Dollars)*	Level 1		Level 2		Level 3		Netting Adjustment (e)			Total		Level 1		Level 2		Level 3		Netting Adjustment (e)			Total
Con Edison
Derivative assets:
Commodity(a)(b)(c)	$	1	$	62	$	17	$	44		$	124	$	3	$	78	$	28	$	(27	)	$	82
Other(a)(b)(d)		167		120		—		—			287		163		116		—		—			279
Total assets	$	168	$	182	$	17	$	44		$	411	$	166	$	194	$	28	$	(27	)	$	361
Derivative liabilities:
Commodity(a)(b)(c)	$	14	$	193	$	6	$	(151	)	$	62	$	18	$	246	$	8	$	(194	)	$	78
CECONY
Derivative assets
Commodity(a)(b)(c)	$	1	$	9	$	12	$	26		$	48	$	1	$	3	$	13	$	21		$	38
Other(a)(b)(d)		159		110		—		—			269		155		106		—		—			261
Total assets	$	160	$	119	$	12	$	26		$	317	$	156	$	109	$	13	$	21		$	299
Derivative liabilities:
Commodity(a)(b)(c)	$	12	$	75	$	—	$	(48	)	$	39	$	16	$	91	$	—	$	(49	)	$	58

(a)	The Companies’ policy is to review the fair value hierarchy and recognize transfers into and transfers out of the levels at the end of each reporting period. There were no transfers between levels 1, 2 and 3 for the three months ended March 31, 2015 and for the year ended December 31, 2014.

(b)

(c)

(d)	Other assets are comprised of assets such as life insurance contracts within the deferred compensation plan and non-qualified retirement plans.

(e)	Amounts represent the impact of legally-enforceable master netting agreements that allow the Companies to net gain and loss positions and cash collateral held or placed with the same counterparties.

Schedule of Commodity Derivatives

The risk management group reports to the Companies’ Vice President and Treasurer.


	Fair Value of Level 3 at March 31, 2015 *(Millions of Dollars)*		Valuation Techniques	Unobservable Inputs	Range
Con Edison – Commodity
Electricity		$ (3)	Discounted Cash Flow	Forward energy prices (a)	$24.50-$121.00 per MWH
			Discounted Cash Flow	Forward capacity prices (a)	$0.75-$8.45 per kW-month
Transmission Congestion Contracts/Financial Transmission Rights		14	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%
				Inter-zonal forward price curves adjusted for historical zonal losses (b)	$(2.65)-$9.48 per MWH
Total Con Edison—Commodity		$ 11
CECONY—Commodity
Transmission Congestion Contracts		$ 12	Discounted Cash Flow	Discount to adjust auction prices for inter-zonal forward price curves (b)	9.6%-57.9%
				Discount to adjust auction prices for historical monthly realized settlements (b)	32.3%-58.2%

(a)	Generally, increases/(decreases) in this input in isolation would result in a higher/(lower) fair value measurement.

(b)	Generally, increases/(decreases) in this input in isolation would result in a lower/(higher) fair value measurement.

Reconciliation of Beginning and Ending Net Balances for Assets and Liabilities Measured at Level 3 Fair Value


	Con Edison						CECONY
*(Millions of Dollars)*	2015			2014			2015			2014
Beginning balance as of January 1,	$	20		$	9		$	13		$	6
Included in earnings		(10	)		50			(2	)		11
Included in regulatory assets and liabilities		—			4			—			4
Purchases		3			8			2			7
Settlements		(2	)		(47	)		(1	)		(15	)
Ending balance as of March 31,	$	11		$	24		$	12		$	13

Variable Interest Entities (Tables)

3 Months Ended

Mar. 31, 2015

Equity Method Investments and Joint Ventures [Abstract]

Summary of VIEs

The following table summarizes the VIEs in which Con Edison Development has entered into as of March 31, 2015:


Project Name (a)	Generating Capacity Owned (MWs AC)		Power Purchase Agreement Term in Years			Year of Initial Investment		Location		Maximum Exposure to Loss (Millions of Dollars)(c)
Pilesgrove		9		n/a	(b)		2010		New Jersey		$26
Mesquite Solar 1		83		20			2013		Arizona		100
Copper Mountain Solar 2		75		25			2013		Nevada		79
Copper Mountain Solar 3		128		20			2014		Nevada		187
California Solar		55		25			2012		California		71
Texas Solar 4		32		25			2014		Texas		55
Broken Bow II		37		25			2014		Nebraska		57

(a)

(b)	Pilesgrove has 3-5 year Solar Renewable Energy Credit hedges in place.

(c)

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References+ Details

Summary of Significant Accounting Policies - Earnings Per Common Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Net income for common stock	$ 370	$ 361
Weighted average common shares outstanding - basic	292.9	292.9
Add: Incremental shares attributable to effect of potentially dilutive securities	1.0	1.2
Adjusted weighted average common shares outstanding - diluted	293.9	294.1
Net Income for common stock per common share - basic	$ 1.26	$ 1.23
Net Income for common stock per common share - diluted	$ 1.26	$ 1.23

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References+ Details

Summary of Significant Accounting Policies -Changes in Accumulated Other Comprehensive Income/(Loss) by Component (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, accumulated OCI, net of taxes	$ (45)	$ (25)
OCI before reclassifications, net of tax	3	2
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax	2	2
Amounts reclassified from accumulated OCI related to pension plan liabilities, Tax	(1)	(1)
TOTAL OTHER COMPREHENSIVE INCOME, NET OF TAXES	5	4
Ending balance, accumulated OCI, net of taxes	(40)	(21)
CECONY [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, accumulated OCI, net of taxes	(11)	(6)
OCI before reclassifications, net of tax	0
Amounts reclassified from accumulated OCI related to pension plan liabilities, net of tax		1
TOTAL OTHER COMPREHENSIVE INCOME, NET OF TAXES		1
Ending balance, accumulated OCI, net of taxes	$ (11)	$ (5)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References+ Details

Summary of Significant Accounting Policies -Changes in Accumulated Other Comprehensive Income/(Loss) by Component (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
OCI before reclassifications, Tax	$ (2)	$ (1)
Amounts reclassified from accumulated OCI related to pension plan liabilities, Tax	$ (1)	$ (1)

Regulatory Matters - Summary of Rate Plan (CECONY-Electric) (Detail) (CECONY [Member], Electric [Member], Scenario, Forecast [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2016
Public Utilities, General Disclosures [Line Items]
Amortizations to income of net regulatory (assets) liabilities	$ 123
Retention of annual transmission congestion revenues	90
Average rate base	18,282
Weighted average cost of capital (after-tax)	6.91%
Authorized return on common equity	9.00%
Earnings sharing percentage	9.60%
Cost of long-term debt	5.09%
Common equity ratio	48.00%
Maximum [Member]
Public Utilities, General Disclosures [Line Items]
Potential penalties	400
T&D [Member]
Public Utilities, General Disclosures [Line Items]
Net utility plant reconciliations	17,929
Storm Hardening [Member]
Public Utilities, General Disclosures [Line Items]
Net utility plant reconciliations	268
Other [Member]
Public Utilities, General Disclosures [Line Items]
Net utility plant reconciliations	$ 2,069

Regulatory Matters - Summary of Rate Plan (CECONY-Electric) (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 Deferred Storm Costs [Member]	Mar. 31, 2015 Electric [Member] CECONY [Member]	Mar. 31, 2015 Electric [Member] Deferred Storm Costs [Member] CECONY [Member]	Dec. 31, 2014 Storm Reserve [Member] Electric [Member] CECONY [Member]	Dec. 31, 2015 Storm Reserve [Member] Electric [Member] Scenario, Forecast [Member] CECONY [Member]
Public Utilities, General Disclosures [Line Items]
Potential refund from customers		$ 249
Revenue requirement				21	21
Annual amortization of regulatory asset			107
Reduction of costs recoverable from customers	$ 4		$ 4

Regulatory Matters - Additional Information (Detail) (Electric [Member], O&R [Member], USD $) In Millions, unless otherwise specified	1 Months Ended
	Mar. 31, 2015	Apr. 30, 2015 Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Electric rate increase (decrease)	$ 0.6
Gas rate increase	14.7	44.2
Return on common equity	8.50%	9.75%
Electric rate increases		$ 34

Regulatory Matters - Other Regulatory Matters - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Public Utilities, General Disclosures [Line Items]
Annual electric revenue subject to potential refund	$ 249
Annual gas revenue subject to potential refund	32
Annual steam revenue subject to potential refund	6
Potential estimated refund to customers	1,747
Construction expenditures overcharge consultant estimate	208
Regulatory liabilities	1,892	1,993
Prudence Proceeding [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities	104	105
CECONY [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities	1,728	1,837
Response and restoration costs	506
Capital expenditures	148
CECONY [Member] \| Prudence Proceeding [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities	104	105
O&R [Member]
Public Utilities, General Disclosures [Line Items]
Response and restoration costs	91
Capital expenditures	15
Storm Damage [Member]
Public Utilities, General Disclosures [Line Items]
Number of customers interrupted electric distribution service	1,400,000
Deferred Storm Costs [Member]
Public Utilities, General Disclosures [Line Items]
Reduction of costs recoverable from customers	$ 4

Regulatory Matters - Regulatory Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Regulatory assets
Regulatory assets - noncurrent	$ 8,906	$ 9,156
Regulatory assets - current	66	148
Total Regulatory Assets	8,972	9,304
Regulatory liabilities
Regulatory liabilities - noncurrent	1,892	1,993
Regulatory liabilities - current	240	187
Total Regulatory Liabilities	2,132	2,180
Unrecognized Pension and Other Postretirement Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	4,593	4,846
Future Income Tax [Member]
Regulatory assets
Regulatory assets - noncurrent	2,289	2,273
Environmental Remediation Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	911	925
Deferred Storm Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	287	319
Revenue Taxes [Member]
Regulatory assets
Regulatory assets - noncurrent	223	219
Surcharge for New York State Assessment [Member]
Regulatory assets
Regulatory assets - noncurrent	96	99
Pension and Other Postretirement Benefits Deferrals [Member]
Regulatory assets
Regulatory assets - noncurrent	61	66
Net Electric Deferrals [Member]
Regulatory assets
Regulatory assets - noncurrent	58	63
Unamortized Loss on Reacquired Debt [Member]
Regulatory assets
Regulatory assets - noncurrent	56	57
Deferred Derivative Losses - Noncurrent [Member]
Regulatory assets
Regulatory assets - noncurrent	44	25
Recoverable Energy Costs - Current [Member]
Regulatory assets
Regulatory assets - noncurrent	42	19
Regulatory assets - current	1	41
O & R Property Tax Reconciliation [Member]
Regulatory assets
Regulatory assets - noncurrent	40	36
O&R Transition Bond Charges [Member]
Regulatory assets
Regulatory assets - noncurrent	25	27
Preferred Stock Redemption [Member]
Regulatory assets
Regulatory assets - noncurrent	27	27
Workers' Compensation [Member]
Regulatory assets
Regulatory assets - noncurrent	9	8
Other [Member]
Regulatory assets
Regulatory assets - noncurrent	145	147
Deferred Derivative Losses - Current [Member]
Regulatory assets
Regulatory assets - current	55	97
Future Income Tax - Current [Member]
Regulatory assets
Regulatory assets - current	10	10
Allowance for Cost of Removal Less Salvage [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	614	598
Property Tax Reconciliation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	297	295
2014 Rate Plan Rate Base Revenue Deferrals [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	153	155
Prudence Proceeding [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	104	105
Pension and Other Post Retirement Benefits Deferrals, Liabilities [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	85	46
Property Tax Refunds [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	76	87
Long-Term Interest Rate Reconciliation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	74	78
Net Unbilled Revenue Deferrals [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	71	138
New York State Income Tax Rate Change [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	63	62
Carrying Charges on Repair Allowance and Bonus Depreciation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	52	58
World Trade Center Settlement Proceeds [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	36	41
Carrying Charges on Transmission and Distribution Net Plant [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	21	21
Electric Excess Earnings [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	19	19
Unrecognized Other Postretirement Benefits Costs [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	15
Other [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	212	290
Refundable Energy Costs - Current [Member]
Regulatory liabilities
Regulatory liabilities - current	177	128
Revenue Decoupling Mechanism [Member]
Regulatory liabilities
Regulatory liabilities - current	30	30
Future Income Tax [Member]
Regulatory liabilities
Regulatory liabilities - current	25	24
Deferred Derivative Gains - Current [Member]
Regulatory liabilities
Regulatory liabilities - current	8	5
CECONY [Member]
Regulatory assets
Regulatory assets - noncurrent	8,251	8,481
Regulatory assets - current	51	132
Total Regulatory Assets	8,302	8,613
Regulatory liabilities
Regulatory liabilities - noncurrent	1,728	1,837
Regulatory liabilities - current	212	142
Total Regulatory Liabilities	1,940	1,979
CECONY [Member] \| Unrecognized Pension and Other Postretirement Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	4,374	4,609
CECONY [Member] \| Future Income Tax [Member]
Regulatory assets
Regulatory assets - noncurrent	2,180	2,166
CECONY [Member] \| Environmental Remediation Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	808	820
CECONY [Member] \| Deferred Storm Costs [Member]
Regulatory assets
Regulatory assets - noncurrent	196	224
CECONY [Member] \| Revenue Taxes [Member]
Regulatory assets
Regulatory assets - noncurrent	211	208
CECONY [Member] \| Surcharge for New York State Assessment [Member]
Regulatory assets
Regulatory assets - noncurrent	90	92
CECONY [Member] \| Pension and Other Postretirement Benefits Deferrals [Member]
Regulatory assets
Regulatory assets - noncurrent	35	42
CECONY [Member] \| Net Electric Deferrals [Member]
Regulatory assets
Regulatory assets - noncurrent	58	63
CECONY [Member] \| Unamortized Loss on Reacquired Debt [Member]
Regulatory assets
Regulatory assets - noncurrent	53	55
CECONY [Member] \| Deferred Derivative Losses - Noncurrent [Member]
Regulatory assets
Regulatory assets - noncurrent	40	23
CECONY [Member] \| Recoverable Energy Costs - Current [Member]
Regulatory assets
Regulatory assets - noncurrent	42	17
Regulatory assets - current		40
CECONY [Member] \| Preferred Stock Redemption [Member]
Regulatory assets
Regulatory assets - noncurrent	27	27
CECONY [Member] \| Workers' Compensation [Member]
Regulatory assets
Regulatory assets - noncurrent	9	8
CECONY [Member] \| Other [Member]
Regulatory assets
Regulatory assets - noncurrent	128	127
CECONY [Member] \| Deferred Derivative Losses - Current [Member]
Regulatory assets
Regulatory assets - current	51	92
CECONY [Member] \| Allowance for Cost of Removal Less Salvage [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	514	499
CECONY [Member] \| Property Tax Reconciliation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	297	295
CECONY [Member] \| 2014 Rate Plan Rate Base Revenue Deferrals [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	153	155
CECONY [Member] \| Prudence Proceeding [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	104	105
CECONY [Member] \| Pension and Other Post Retirement Benefits Deferrals, Liabilities [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	64	37
CECONY [Member] \| Property Tax Refunds [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	76	87
CECONY [Member] \| Long-Term Interest Rate Reconciliation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	74	78
CECONY [Member] \| Net Unbilled Revenue Deferrals [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	71	138
CECONY [Member] \| New York State Income Tax Rate Change [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	60	59
CECONY [Member] \| Carrying Charges on Repair Allowance and Bonus Depreciation [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	50	57
CECONY [Member] \| World Trade Center Settlement Proceeds [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	36	41
CECONY [Member] \| Carrying Charges on Transmission and Distribution Net Plant [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	21	20
CECONY [Member] \| Electric Excess Earnings [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	18	18
CECONY [Member] \| Unrecognized Other Postretirement Benefits Costs [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	13
CECONY [Member] \| Other [Member]
Regulatory liabilities
Regulatory liabilities - noncurrent	177	248
CECONY [Member] \| Refundable Energy Costs - Current [Member]
Regulatory liabilities
Regulatory liabilities - current	152	84
CECONY [Member] \| Revenue Decoupling Mechanism [Member]
Regulatory liabilities
Regulatory liabilities - current	30	30
CECONY [Member] \| Future Income Tax [Member]
Regulatory liabilities
Regulatory liabilities - current	24	24
CECONY [Member] \| Deferred Derivative Gains - Current [Member]
Regulatory liabilities
Regulatory liabilities - current	$ 6	$ 4

Capitalization - Carrying Amounts and Fair Values of Long-Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Carrying Amount	$ 12,190	$ 12,191
Fair Value	14,224	13,998
CECONY [Member]
Debt Instrument [Line Items]
Carrying Amount	11,214	11,214
Fair Value	$ 13,066	$ 12,846

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References+ Details

Capitalization - Additional Information (Detail) (USD $) In Millions, unless otherwise specified								3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2015 Level 2 [Member]	Mar. 31, 2015 Level 3 [Member]	Mar. 31, 2015 CECONY [Member]	Dec. 31, 2014 CECONY [Member]	Mar. 31, 2015 CECONY [Member] Level 2 [Member]	Mar. 31, 2015 CECONY [Member] Level 3 [Member]
Schedule of Capitalization [Line Items]
Long-term debt, fair value	$ 14,224	$ 13,998	$ 13,588	$ 636	$ 13,066	$ 12,846	$ 12,430	$ 636
Tax-exempt debt								$ 636

Short-Term Borrowing - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Short-term Debt [Line Items]
Commercial paper, outstanding	$ 519,000,000	$ 800,000,000
Weighted average interest rate	0.50%	0.40%
Letters of credit outstanding under the Credit Agreement	61,000,000	11,000,000
Loans outstanding under credit agreement	0	0
CECONY [Member]
Short-term Debt [Line Items]
Commercial paper, outstanding	268,000,000	450,000,000
Weighted average interest rate	0.50%	0.40%
Letters of credit outstanding under the Credit Agreement	$ 11,000,000	$ 11,000,000

- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References+ Details

Pension Benefits - Total Periodic Benefit Costs (Detail) (Pension Benefits [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost - including administrative expenses	$ 74	$ 57
Interest cost on projected benefit obligation	144	143
Expected return on plan assets	(222)	(208)
Recognition of net actuarial loss	194	154
Recognition of prior service costs	1	1
TOTAL PERIODIC BENEFIT COST	191	147
Cost capitalized	(68)	(51)
Reconciliation to rate level	(24)	26
Cost charged to operating expenses	99	122
CECONY [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost - including administrative expenses	70	53
Interest cost on projected benefit obligation	135	134
Expected return on plan assets	(210)	(197)
Recognition of net actuarial loss	183	146
Recognition of prior service costs		1
TOTAL PERIODIC BENEFIT COST	178	137
Cost capitalized	(65)	(49)
Reconciliation to rate level	(24)	23
Cost charged to operating expenses	$ 89	$ 111

Pension Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 750
CECONY [Member] \| Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	697
Contributions	204
CECONY [Member] \| Non-qualified Supplemental Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 16

Other Postretirement Benefits - Total Periodic Postretirement Benefit Costs (Detail) (Other Postretirement Benefits [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5	$ 5
Interest cost on accumulated other postretirement benefit obligation	13	15
Expected return on plan assets	(20)	(19)
Recognition of net actuarial loss	8	14
Recognition of prior service cost	(5)	(5)
TOTAL PERIODIC OTHER POSTRETIREMENT BENEFIT COST	1	10
Cost capitalized	(1)	(4)
Reconciliation to rate level	4	3
Cost charged to operating expenses	4	9
CECONY [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4
Interest cost on accumulated other postretirement benefit obligation	11	13
Expected return on plan assets	(17)	(17)
Recognition of net actuarial loss	7	13
Recognition of prior service cost	(4)	(4)
TOTAL PERIODIC OTHER POSTRETIREMENT BENEFIT COST	1	9
Cost capitalized	(1)	(3)
Reconciliation to rate level	2
Cost charged to operating expenses	$ 2	$ 6

Environmental Matters - Accrued Liabilities and Regulatory Assets (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accrued Liabilities:
Accrued Liabilities	$ 758	$ 764
Regulatory assets	8,972	9,304
Manufactured Gas Plant Sites [Member]
Accrued Liabilities:
Accrued Liabilities	678	684
Other Superfund Sites [Member]
Accrued Liabilities:
Accrued Liabilities	80	80
Superfund Sites [Member]
Accrued Liabilities:
Accrued Liabilities	758	764
Regulatory assets	911	925
CECONY [Member]
Accrued Liabilities:
Accrued Liabilities	662	666
Regulatory assets	8,302	8,613
CECONY [Member] \| Manufactured Gas Plant Sites [Member]
Accrued Liabilities:
Accrued Liabilities	582	587
CECONY [Member] \| Other Superfund Sites [Member]
Accrued Liabilities:
Accrued Liabilities	80	79
CECONY [Member] \| Superfund Sites [Member]
Accrued Liabilities:
Accrued Liabilities	662	666
Regulatory assets	$ 808	$ 820

- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

+ References+ Details

Environmental Matters - Environmental Remediation Costs (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Environmental Exit Cost [Line Items]
Remediation costs incurred	$ 7	$ 9
Insurance recoveries received		5
CECONY [Member]
Environmental Exit Cost [Line Items]
Remediation costs incurred	6	8
Insurance recoveries received		$ 5

Environmental Matters - Additional Information (Detail) (USD $)	3 Months Ended		3 Months Ended
	Mar. 31, 2015 Asbestos Proceedings [Member]	Dec. 31, 2014 Manufactured Gas Plant Sites [Member] Maximum [Member]	Mar. 31, 2015 CECONY [Member] Asbestos Proceedings [Member]	Dec. 31, 2014 CECONY [Member] Manufactured Gas Plant Sites [Member] Maximum [Member]
Site Contingency [Line Items]
Estimated aggregate undiscounted potential liability related environmental contaminants		$ 2,700,000,000		$ 2,500,000,000
Estimated undiscounted asbestos liability	$ 8,000,000		$ 7,000,000
Estimated undiscounted asbestos liability in year	15 years		15 years

Environmental Matters - Accrued Liability for Asbestos Suits and Workers' Compensation Proceedings (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Site Contingency [Line Items]
Regulatory assets	$ 8,972	$ 9,304
Asbestos Suits [Member]
Site Contingency [Line Items]
Accrued liability	8	8
Regulatory assets	8	8
Workers' Compensation [Member]
Site Contingency [Line Items]
Accrued liability	84	83
Regulatory assets	9	8
CECONY [Member]
Site Contingency [Line Items]
Regulatory assets	8,302	8,613
CECONY [Member] \| Asbestos Suits [Member]
Site Contingency [Line Items]
Accrued liability	7	7
Regulatory assets	7	7
CECONY [Member] \| Workers' Compensation [Member]
Site Contingency [Line Items]
Accrued liability	79	78
Regulatory assets	$ 9	$ 8

Other Material Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended
	Jul. 31, 2007 Person	Mar. 31, 2015 People Lawsuits	Dec. 31, 2014
Guarantor Obligations [Line Items]
Number of person died in steam ruptured	1
Number of suits pending against the company		90
Estimated accrued liability for suits		$ 50,000,000
Insurance receivable for suits		50,000,000
Description of explosion and fire incident		On March 12, 2014, two multi-use five-story tall buildings located on Park Avenue between 116thand 117thStreet in Manhattan were destroyed by an explosion and fire. CECONY had delivered gas to the buildings through service lines from a distribution main located below ground on Park Avenue. Eight people died and more than 48 people were injured. Additional buildings were also damaged.
Number of people died in explosion and fire incident		8
Number of people injured in explosion and fire incident		48
Guarantee obligations maximum exposure		2,559,000,000	2,547,000,000
Ownership interest, percentage			45.70%
Estimated project cost percentage		175.00%
Manhattan Explosion and Fire [Member]
Guarantor Obligations [Line Items]
Number of suits pending against the company		35
Other [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure		30,000,000
Electric provider obligation to Public Utility Commission of Texas		5,000,000
Indemnity agreements amount		25,000,000
Con Edison Development [Member]
Guarantor Obligations [Line Items]
Percentage of variable interests		50.00%
Number of guaranteed payments		2
Con Edison Development [Member] \| Guarantee One [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure		35,000,000
Con Edison Development [Member] \| Guarantee Two [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure		15,000,000
Construction and Operation of Solar Energy Facilities [Member]
Guarantor Obligations [Line Items]
Guarantees issued		$ 3,000,000

Other Material Contingencies - Total Guarantees (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	$ 2,559,000,000	$ 2,547,000,000
NY Transco [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	1,360,000,000
Energy Transactions [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	958,000,000
Renewable Electric Production Projects [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	211,000,000
Other [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	30,000,000
0 - 3 years [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	2,424,000,000
0 - 3 years [Member] \| NY Transco [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	1,360,000,000
0 - 3 years [Member] \| Energy Transactions [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	830,000,000
0 - 3 years [Member] \| Renewable Electric Production Projects [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	204,000,000
0 - 3 years [Member] \| Other [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	30,000,000
4 - 10 years [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	38,000,000
4 - 10 years [Member] \| Energy Transactions [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	38,000,000
Greater than 10 years [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	97,000,000
Greater than 10 years [Member] \| Energy Transactions [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	90,000,000
Greater than 10 years [Member] \| Renewable Electric Production Projects [Member]
Guarantor Obligations [Line Items]
Guarantee obligations maximum exposure	$ 7,000,000

Income Tax - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Taxes Disclosure [Line Items]
INCOME TAX EXPENSE	$ 199	$ 198
Effective tax rate	35.00%	35.00%
Estimated liability for uncertain tax positions	34
Uncertain tax positions, reasonably possible to resolve within twelve months	25
Uncertain tax positions, reasonably possible to resolve within twelve months, net of federal taxes	16
Total amount of unrecognized tax benefits, if recognized, that would reduce effective tax rate	34
Total amount of unrecognized tax benefits, if recognized, that would reduce effective tax rate, net of federal taxes	22
CECONY [Member]
Income Taxes Disclosure [Line Items]
INCOME TAX EXPENSE	192	184
Effective tax rate	36.00%	36.00%
Estimated liability for uncertain tax positions	2
Uncertain tax positions, reasonably possible to resolve within twelve months	2
Uncertain tax positions, reasonably possible to resolve within twelve months, net of federal taxes	$ 1

Financial Information by Business Segment - Financial Data for Business Segments (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Operating revenues	$ 3,616	$ 3,789
Depreciation and amortization	279	261
Operating income	726	685
CECONY [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,010	3,204
Depreciation and amortization	257	240
Operating income	684	643
CECONY [Member] \| Electric [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	202	189
Operating income	279	257
CECONY [Member] \| Gas [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	35	32
Operating income	241	233
CECONY [Member] \| Steam [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	20	19
Operating income	164	153
O&R [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	17	14
Operating income	45	39
O&R [Member] \| Electric [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	12	10
Operating income	18	12
O&R [Member] \| Gas [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	5	4
Operating income	27	27
Competitive Energy Businesses [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	5	7
Operating income	(3)	2
Other [Member]
Segment Reporting Information [Line Items]
Operating income		1
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,616	3,789
Operating Segments [Member] \| CECONY [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,010	3,204
Operating Segments [Member] \| CECONY [Member] \| Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,980	2,074
Operating Segments [Member] \| CECONY [Member] \| Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues	655	789
Operating Segments [Member] \| CECONY [Member] \| Steam [Member]
Segment Reporting Information [Line Items]
Operating revenues	375	341
Operating Segments [Member] \| O&R [Member]
Segment Reporting Information [Line Items]
Operating revenues	233	256
Operating Segments [Member] \| O&R [Member] \| Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues	156	163
Operating Segments [Member] \| O&R [Member] \| Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues	77	93
Operating Segments [Member] \| Competitive Energy Businesses [Member]
Segment Reporting Information [Line Items]
Operating revenues	374	329
Operating Segments [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	(1)
Inter-Segment Revenues [Member] \| CECONY [Member]
Segment Reporting Information [Line Items]
Operating revenues	(27)	(25)
Inter-Segment Revenues [Member] \| CECONY [Member] \| Electric [Member]
Segment Reporting Information [Line Items]
Operating revenues	4	4
Inter-Segment Revenues [Member] \| CECONY [Member] \| Gas [Member]
Segment Reporting Information [Line Items]
Operating revenues	1	1
Inter-Segment Revenues [Member] \| CECONY [Member] \| Steam [Member]
Segment Reporting Information [Line Items]
Operating revenues	22	20
Inter-Segment Revenues [Member] \| Competitive Energy Businesses [Member]
Segment Reporting Information [Line Items]
Operating revenues	(3)	3
Inter-Segment Revenues [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	$ 3	$ (3)

Derivative Instruments and Hedging Activities - Fair Values of Commodity Derivatives Including Offsetting of Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	$ (132)	$ (163)
Gross Amounts Offset	158	140
Net Amounts of Assets/(Liabilities)	26	(23)
Fair Value of Derivative Assets, Current [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	108	111
Gross Amounts Offset	(23)	(67)
Net Amounts of Assets/(Liabilities)	85	44
Fair Value of Derivative Assets, Noncurrent [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	30	34
Gross Amounts Offset	(28)	(23)
Net Amounts of Assets/(Liabilities)	2	11
Fair Value of Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	138	145
Gross Amounts Offset	(51)	(90)
Net Amounts of Assets/(Liabilities)	87	55
Fair Value of Derivative Liabilities, Current [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(174)	(242)
Gross Amounts Offset	137	139
Net Amounts of Assets/(Liabilities)	(37)	(103)
Fair Value of Derivative Liabilities, Noncurrent [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(96)	(66)
Gross Amounts Offset	72	91
Net Amounts of Assets/(Liabilities)	(24)	25
Fair Value of Derivative Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(270)	(308)
Gross Amounts Offset	209	230
Net Amounts of Assets/(Liabilities)	(61)	(78)
CECONY [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(65)	(90)
Gross Amounts Offset	39	45
Net Amounts of Assets/(Liabilities)	(26)	(45)
CECONY [Member] \| Fair Value of Derivative Assets, Current [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	40	26
Gross Amounts Offset	(29)	(15)
Net Amounts of Assets/(Liabilities)	11	11
CECONY [Member] \| Fair Value of Derivative Assets, Noncurrent [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	17	22
Gross Amounts Offset	(15)	(20)
Net Amounts of Assets/(Liabilities)	2	2
CECONY [Member] \| Fair Value of Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	57	48
Gross Amounts Offset	(44)	(35)
Net Amounts of Assets/(Liabilities)	13	13
CECONY [Member] \| Fair Value of Derivative Liabilities, Current [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(69)	(96)
Gross Amounts Offset	46	48
Net Amounts of Assets/(Liabilities)	(23)	(48)
CECONY [Member] \| Fair Value of Derivative Liabilities, Noncurrent [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(53)	(42)
Gross Amounts Offset	37	32
Net Amounts of Assets/(Liabilities)	(16)	(10)
CECONY [Member] \| Fair Value of Derivative Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts of Recognized Assets/(Liabilities)	(122)	(138)
Gross Amounts Offset	83	80
Net Amounts of Assets/(Liabilities)	$ (39)	$ (58)

Derivative Instruments and Hedging Activities - Realized and Unrealized Gains or Losses on Commodity Derivatives (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	$ 3	$ 34
Total deferred gains/(losses)	24	113
Net deferred gains/(losses)	27	147
Pre-tax gain/(loss) recognized in income
Total pre-tax gain/(loss) recognized in income	21	137
Deferred Derivative Gains - Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	3	30
Deferred Derivative Gains, Noncurrent [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)		4
Deferred Derivative Losses, Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	43	17
Recoverable Energy Costs - Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)		94
Deferred Derivative Losses, Noncurrent [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	(19)	2
CECONY [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	3	29
Total deferred gains/(losses)	23	96
Net deferred gains/(losses)	26	125
CECONY [Member] \| Deferred Derivative Gains - Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	3	25
CECONY [Member] \| Deferred Derivative Gains, Noncurrent [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)		4
CECONY [Member] \| Deferred Derivative Losses, Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	41	17
CECONY [Member] \| Recoverable Energy Costs - Current [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	(2)	77
CECONY [Member] \| Deferred Derivative Losses, Noncurrent [Member]
Pre-tax gains/(losses) deferred in accordance with accounting rules for regulated operations:
Total deferred gains/(losses)	(16)	2
Purchased Power Costs [Member]
Pre-tax gain/(loss) recognized in income
Total pre-tax gain/(loss) recognized in income	21	175
Gas Purchased for Resale [Member]
Pre-tax gain/(loss) recognized in income
Total pre-tax gain/(loss) recognized in income	(42)	(14)
Non-utility Revenue [Member]
Pre-tax gain/(loss) recognized in income
Total pre-tax gain/(loss) recognized in income	$ 42	$ (24)

Derivative Instruments and Hedging Activities - Realized and Unrealized Gains or Losses on Commodity Derivatives (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Non Utility Operating Revenue [Member]
Derivatives, Fair Value [Line Items]
Unrealized gain (loss) on derivatives	$ (4)
Purchased Power Costs [Member]
Derivatives, Fair Value [Line Items]
Unrealized gain (loss) on derivatives	$ 12	$ 20

Derivative Instruments and Hedging Activities - Hedged Volume of Derivative Transactions (Detail)	3 Months Ended
	Mar. 31, 2015 MWh
Electric Energy Derivative [Member]
Derivatives, Fair Value [Line Items]
MWHs	19,565,133
Electric Capacity Derivative [Member]
Derivatives, Fair Value [Line Items]
MWs	6,751
Natural Gas Derivative [Member]
Derivatives, Fair Value [Line Items]
Dths	54,964,831
Refined Fuels [Member]
Derivatives, Fair Value [Line Items]
Gallons	2,352,000
CECONY [Member] \| Electric Energy Derivative [Member]
Derivatives, Fair Value [Line Items]
MWHs	6,640,525
CECONY [Member] \| Electric Capacity Derivative [Member]
Derivatives, Fair Value [Line Items]
MWs	2,100
CECONY [Member] \| Natural Gas Derivative [Member]
Derivatives, Fair Value [Line Items]
Dths	53,860,000
CECONY [Member] \| Refined Fuels [Member]
Derivatives, Fair Value [Line Items]
Gallons	2,352,000

Derivative Instruments and Hedging Activities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Investment Holdings [Line Items]
Energy supply and hedging activities credit exposure total	$ 212
Makeup of net credit exposure independent system operators	92
Makeup of net credit exposure with commodity exchange brokers	108
Makeup of net credit exposure with investment-grade counterparties	8
Makeup of net credit exposure non-investment grade/non-rated counterparties	4
CECONY [Member]
Investment Holdings [Line Items]
Energy supply and hedging activities credit exposure total	$ 35

Derivative Instruments and Hedging Activities - Aggregate Fair Value of Companies' Derivative Instruments with Credit-Risk-Related Contingent Features (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Derivatives, Fair Value [Line Items]
Aggregate fair value - net liabilities	$ 58
Collateral posted	5
Downgrade to Below Investment Grade from Current Ratings [Member]
Derivatives, Fair Value [Line Items]
Derivatives in net liability position additional collateral	73
CECONY [Member]
Derivatives, Fair Value [Line Items]
Aggregate fair value - net liabilities	40
CECONY [Member] \| Downgrade to Below Investment Grade from Current Ratings [Member]
Derivatives, Fair Value [Line Items]
Derivatives in net liability position additional collateral	$ 46

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 411	$ 361
CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	317	299
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	168	166
Level 1 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	160	156
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	182	194
Level 2 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	119	109
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	17	28
Level 3 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	12	13
Commodity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	124	82
Derivative liabilities	62	78
Commodity [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	48	38
Derivative liabilities	39	58
Commodity [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	1	3
Derivative liabilities	14	18
Commodity [Member] \| Level 1 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	1	1
Derivative liabilities	12	16
Commodity [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	62	78
Derivative liabilities	193	246
Commodity [Member] \| Level 2 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	9	3
Derivative liabilities	75	91
Commodity [Member] \| Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	17	28
Derivative liabilities	6	8
Commodity [Member] \| Level 3 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	12	13
Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	287	279
Other [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	269	261
Other [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	167	163
Other [Member] \| Level 1 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	159	155
Other [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	120	116
Other [Member] \| Level 2 [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	110	106
Netting Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	44	(27)
Netting Adjustments [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	26	21
Netting Adjustments [Member] \| Commodity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	44	(27)
Derivative liabilities	(151)	(194)
Netting Adjustments [Member] \| Commodity [Member] \| CECONY [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	26	21
Derivative liabilities	$ (48)	$ (49)

- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

Fair Value Measurements - Schedule of Commodity Derivatives (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Valuation Techniques	Discounted Cash Flow
Electricity [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Valuation Techniques	Discounted Cash Flow
Transmission Congestion Contracts/Financial Transmission Rights [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Valuation Techniques	Discounted Cash Flow
Minimum [Member] \| Discount to Adjust Auction Prices for Inter-Zonal Forward Price Curves [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	9.60%
Minimum [Member] \| Discount to Adjust Auction Prices for Historical Monthly Realized Settlements [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	32.30%
Minimum [Member] \| Inter-Zonal Forward Price Curves Adjusted for Historical Zonal Losses [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	(2.65)
Minimum [Member] \| Forward Energy Prices [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	24.50
Minimum [Member] \| Forward Capacity Prices [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	0.75
Maximum [Member] \| Discount to Adjust Auction Prices for Inter-Zonal Forward Price Curves [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	(57.90%)
Maximum [Member] \| Discount to Adjust Auction Prices for Historical Monthly Realized Settlements [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	(58.20%)
Maximum [Member] \| Inter-Zonal Forward Price Curves Adjusted for Historical Zonal Losses [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	9.48
Maximum [Member] \| Forward Energy Prices [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	121
Maximum [Member] \| Forward Capacity Prices [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range	8.45
Level 3 [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Fair Value of commodity derivatives	$ 11
Level 3 [Member] \| Electricity [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Fair Value of commodity derivatives	(3)
Level 3 [Member] \| Transmission Congestion Contracts/Financial Transmission Rights [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Fair Value of commodity derivatives	14
CECONY [Member] \| Transmission Congestion Contracts [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Valuation Techniques	Discounted Cash Flow
CECONY [Member] \| Minimum [Member] \| Discount to Adjust Auction Prices for Inter-Zonal Forward Price Curves [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	9.60%
CECONY [Member] \| Minimum [Member] \| Discount to Adjust Auction Prices for Historical Monthly Realized Settlements [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	32.30%
CECONY [Member] \| Maximum [Member] \| Discount to Adjust Auction Prices for Inter-Zonal Forward Price Curves [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	(57.90%)
CECONY [Member] \| Maximum [Member] \| Discount to Adjust Auction Prices for Historical Monthly Realized Settlements [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Unobservable Inputs Range in percentage	(58.20%)
CECONY [Member] \| Level 3 [Member] \| Transmission Congestion Contracts [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Fair Value of commodity derivatives	$ 12

Fair Value Measurements - Reconciliation of Beginning and Ending Net Balances for Assets and Liabilities Measured at Level 3 Fair Value (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 20	$ 9
Included in earnings	(10)	50
Included in regulatory assets and liabilities		4
Purchases	3	8
Settlements	(2)	(47)
Ending balance	11	24
CECONY [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	13	6
Included in earnings	(2)	11
Included in regulatory assets and liabilities		4
Purchases	2	7
Settlements	(1)	(15)
Ending balance	$ 12	$ 13

Fair Value Measurements - Additional Information (Detail) (Purchased Power Costs [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, assets measured on recurring basis, change in unrealized gain (loss)	$ (5)	$ 8
Competitive Energy Businesses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gain (loss) on Level 3 energy derivative liabilities	$ (8)	$ 39

Variable Interest Entities - Additional Information (Detail) (USD $)	Mar. 31, 2015 Cogen Technologies Linden Venture, LP [Member]	Mar. 31, 2015 Brooklyn Navy Yard Cogeneration Partners, LP [Member]	Mar. 31, 2015 Indeck Energy Services of Corinth, Inc [Member]	Dec. 31, 2014 CECONY [Member] VIE
Variable Interest Entity [Line Items]
Number of potential VIEs, long-term electricity purchase agreements				3
Maximum exposure to loss	$ 105,000,000	$ 30,000,000	$ 15,000,000

Variable Interest Entities - Summary of VIEs (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015 MW
Variable Interest Entity, Not Primary Beneficiary [Member] \| Pilesgrove [Member] \| New Jersey [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	9
Year of Initial Investment	2010
Maximum exposure to loss	$ 26,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] \| Mesquite Solar 1 [Member] \| Arizona [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	83
Power Purchase Agreement Term in Years	20 years
Year of Initial Investment	2013
Maximum exposure to loss	100,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] \| Copper Mountain Solar 2 [Member] \| Nevada [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	75
Power Purchase Agreement Term in Years	25 years
Year of Initial Investment	2013
Maximum exposure to loss	79,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] \| Copper Mountain Solar 3 [Member] \| Nevada [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	128
Power Purchase Agreement Term in Years	20 years
Year of Initial Investment	2014
Maximum exposure to loss	187,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] \| California Solar [Member] \| California [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	55
Power Purchase Agreement Term in Years	25 years
Year of Initial Investment	2012
Maximum exposure to loss	71,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] \| Broken Bow II [Member] \| Nebraska [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	37
Power Purchase Agreement Term in Years	25 years
Year of Initial Investment	2014
Maximum exposure to loss	57,000,000
Variable Interest Entity, Primary Beneficiary [Member] \| Texas Solar 4 [Member] \| Texas [Member]
Variable Interest Entity [Line Items]
Generating Capacity Owned (MWs AC)	32
Power Purchase Agreement Term in Years	25 years
Year of Initial Investment	2014
Maximum exposure to loss	$ 55,000,000

Variable Interest Entities - Summary of VIEs (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Variable Interest Entity, Primary Beneficiary [Member] \| Texas Solar 4 [Member]
Variable Interest Entity [Line Items]
Percentage of variable interests	80.00%
VIEs, noncontrolling interest	$ 9
Variable Interest Entity, Not Primary Beneficiary, Aggregated Disclosure [Member]
Variable Interest Entity [Line Items]
Percentage of variable interests	50.00%
Minimum [Member] \| Solar Renewable Energy Credit Hedge [Member] \| Pilesgrove [Member]
Variable Interest Entity [Line Items]
Renewable Energy Credit	3 years
Maximum [Member] \| Solar Renewable Energy Credit Hedge [Member] \| Pilesgrove [Member]
Variable Interest Entity [Line Items]
Renewable Energy Credit	5 years

Derivative Instruments and Hedging Activities - Fair Values of Commodity Derivatives Including Offsetting of Assets and Liabilities (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Margin deposits	$ 37	$ 27
CECONY [Member]
Derivatives, Fair Value [Line Items]
Margin deposits	$ 35	$ 25

Derivative Instruments and Hedging Activities - Aggregate Fair Value of Companies' Derivative Instruments with Credit-Risk-Related Contingent Features (Parenthetical) (Detail) (Downgrade to Below Investment Grade from Current Ratings [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Downgrade to Below Investment Grade from Current Ratings [Member]
Derivatives, Fair Value [Line Items]
Derivatives in net asset position additional collateral	$ 20