Consolidated Balance Sheet (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
NON-UTILITY PLANT
Non-utility property, less accumulated depreciation	$ 581	$ 555
Construction work in progress	29	83
NET PLANT	27,955	26,939
OTHER NONCURRENT ASSETS
Goodwill	429	429
Intangible assets, less accumulated amortization of $4 in 2013 and 2012	4	2
Regulatory assets	9,190	9,705
Other deferred charges and noncurrent assets	238	216
TOTAL OTHER NONCURRENT ASSETS	9,861	10,352
TOTAL ASSETS	41,964	41,209
CURRENT ASSETS
Cash and temporary cash investments	74	394
Special deposits	375	70
Accounts receivable - customers, less allowance for uncollectible accounts	1,273	1,222
Other receivables, less allowance for uncollectible accounts	257	228
Accrued unbilled revenue	425	516
Fuel oil, gas in storage, materials and supplies, at average cost	368	330
Prepayments	521	159
Regulatory assets	46	74
Deferred tax assets - current	186	296
Other current assets	179	162
TOTAL CURRENT ASSETS	3,704	3,451
INVESTMENTS	444	467
UTILITY PLANT, AT ORIGINAL COST
General	2,301	2,302
TOTAL	32,847	31,847
Less: Accumulated depreciation	6,952	6,573
Net	25,895	25,274
Construction work in progress	1,450	1,027
NET UTILITY PLANT	27,345	26,301
CURRENT LIABILITIES
Long-term debt due within one year	483	706
Notes payable	1,220	539
Accounts payable	925	1,215
Customer deposits	316	304
Accrued taxes	379	162
Accrued interest	324	153
Accrued wages	93	94
Fair value of derivative liabilities	25	47
Uncertain income tax liabilities		44
Regulatory liabilities	117	183
Other current liabilities	491	498
TOTAL CURRENT LIABILITIES	4,373	3,945
NONCURRENT LIABILITIES
Obligations under capital leases	2	2
Provision for injuries and damages	195	149
Pensions and retiree benefits	3,816	4,678
Superfund and other environmental costs	512	545
Asset retirement obligations	164	159
Fair value of derivative liabilities	29	31
Uncertain income tax liabilities	8
Other noncurrent liabilities	120	125
TOTAL NONCURRENT LIABILITIES	4,846	5,689
DEFERRED CREDITS AND REGULATORY LIABILITIES
Deferred income taxes and investment tax credits	8,481	8,372
Regulatory liabilities	1,557	1,202
Other deferred credits	48	70
TOTAL DEFERRED CREDITS AND REGULATORY LIABILITIES	10,086	9,644
LONG-TERM DEBT	10,493	10,062
COMMON SHAREHOLDER'S EQUITY (See Statement of Common Shareholder's Equity)	12,166	11,869
TOTAL LIABILITIES AND SHAREHOLDER'S EQUITY	41,964	41,209
CECONY [Member]
NON-UTILITY PLANT
Non-utility property, less accumulated depreciation	5	6
NET PLANT	25,735	24,745
OTHER NONCURRENT ASSETS
Regulatory assets	8,497	8,972
Other deferred charges and noncurrent assets	171	174
TOTAL OTHER NONCURRENT ASSETS	8,668	9,146
TOTAL ASSETS	37,375	36,885
CURRENT ASSETS
Cash and temporary cash investments	38	353
Special deposits	86	65
Accounts receivable - customers, less allowance for uncollectible accounts	1,147	1,108
Other receivables, less allowance for uncollectible accounts	142	106
Accrued unbilled revenue	329	406
Accounts receivable from affiliated companies	35	61
Fuel oil, gas in storage, materials and supplies, at average cost	311	285
Prepayments	428	81
Regulatory assets	42	60
Deferred tax assets - current	123	193
Other current assets	60	69
TOTAL CURRENT ASSETS	2,741	2,787
INVESTMENTS	231	207
UTILITY PLANT, AT ORIGINAL COST
General	2,123	2,126
TOTAL	30,714	29,801
Less: Accumulated depreciation	6,357	6,009
Net	24,357	23,792
Construction work in progress	1,373	947
NET UTILITY PLANT	25,730	24,739
CURRENT LIABILITIES
Long-term debt due within one year	475	700
Notes payable	1,042	421
Accounts payable	737	989
Accounts payable to affiliated companies	16	22
Customer deposits	304	292
Accrued taxes	20	37
Accrued taxes to affiliated companies	140	215
Accrued interest	176	133
Accrued wages	89	84
Fair value of derivative liabilities	19	28
Uncertain income tax liabilities		36
Regulatory liabilities	86	145
Other current liabilities	419	410
TOTAL CURRENT LIABILITIES	3,523	3,512
NONCURRENT LIABILITIES
Obligations under capital leases	2	2
Provision for injuries and damages	188	141
Pensions and retiree benefits	3,414	4,220
Superfund and other environmental costs	403	433
Asset retirement obligations	163	158
Fair value of derivative liabilities	7	11
Other noncurrent liabilities	109	115
TOTAL NONCURRENT LIABILITIES	4,286	5,080
DEFERRED CREDITS AND REGULATORY LIABILITIES
Deferred income taxes and investment tax credits	7,888	7,452
Regulatory liabilities	1,431	1,077
Other deferred credits	43	67
TOTAL DEFERRED CREDITS AND REGULATORY LIABILITIES	9,362	8,596
LONG-TERM DEBT	9,366	9,145
COMMON SHAREHOLDER'S EQUITY (See Statement of Common Shareholder's Equity)	10,838	10,552
TOTAL LIABILITIES AND SHAREHOLDER'S EQUITY	37,375	36,885
Electric [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	23,041	22,376
Electric [Member] | CECONY [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	21,680	21,079
Gas [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	5,388	5,120
Gas [Member] | CECONY [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	4,794	4,547
Steam [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	2,117	2,049
Steam [Member] | CECONY [Member]
UTILITY PLANT, AT ORIGINAL COST
Utility plant, at original cost	$ 2,117	$ 2,049