Consolidated Statement of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
OPERATING ACTIVITIES
NET INCOME	$ 1,092us-gaap_NetIncomeLoss	$ 1,062us-gaap_NetIncomeLoss	$ 1,141us-gaap_NetIncomeLoss
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	1,071us-gaap_DepreciationAndAmortization	1,024us-gaap_DepreciationAndAmortization	955us-gaap_DepreciationAndAmortization
Deferred income taxes	518us-gaap_DeferredIncomeTaxExpenseBenefit	40us-gaap_DeferredIncomeTaxExpenseBenefit	584us-gaap_DeferredIncomeTaxExpenseBenefit
Rate case amortization and accruals	102us-gaap_AdjustmentForAmortization	10us-gaap_AdjustmentForAmortization	42us-gaap_AdjustmentForAmortization
Common equity component of allowance for funds used during construction	(2)	(4)	(4)
Net derivative (gains)/losses	128us-gaap_GainLossOnSaleOfDerivatives	(74)us-gaap_GainLossOnSaleOfDerivatives	(68)us-gaap_GainLossOnSaleOfDerivatives
Pre-tax gains on termination of LILO transactions		(95)us-gaap_GainLossOnContractTermination
Pre-tax gain on sale of solar electric production projects	(45)us-gaap_GainOnSaleOfInvestments
Other non-cash items (net)	(35)us-gaap_OtherNoncashIncomeExpense	91us-gaap_OtherNoncashIncomeExpense	52us-gaap_OtherNoncashIncomeExpense
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers, less allowance for uncollectibles	44	(29)	(99)
Special deposits	312us-gaap_IncreaseDecreaseInDeposits	(257)us-gaap_IncreaseDecreaseInDeposits	(13)us-gaap_IncreaseDecreaseInDeposits
Materials and supplies, including fuel oil and gas in storage	(10)us-gaap_IncreaseDecreaseInInventories	(33)us-gaap_IncreaseDecreaseInInventories	26us-gaap_IncreaseDecreaseInInventories
Other receivables and other current assets	4	34	40
Income taxes receivable	(224)
Prepayments	(27)	23	(14)
Accounts payable	(9)	(118)	111
Pensions and retiree benefits obligations (net)	822	829	903
Pensions and retiree benefits contributions	(584)	(887)	(870)
Accrued taxes	(404)	314	(26)
Accrued interest	(113)	96	(7)
Superfund and environmental remediation costs (net)	28	(4)	7
Deferred charges, noncurrent assets and other regulatory assets	(339)	(141)	(337)
Deferred credits and other regulatory liabilities	495	627	92
Other current and noncurrent liabilities	7	44	84
Net Cash Flows from Operating Activities	2,831	2,552	2,599
INVESTING ACTIVITIES
Utility construction expenditures	(2,239)	(2,339)	(1,917)
Cost of removal less salvage	(216)	(217)	(175)
Non-utility construction expenditures	(180)	(199)	(152)
Investments in renewable electric production projects	(283)us-gaap_PaymentsToAcquireProjects	(175)us-gaap_PaymentsToAcquireProjects	(309)us-gaap_PaymentsToAcquireProjects
Proceeds from grants related to solar electric production projects	36	93	30
Proceeds from sale of solar electric production projects	108
Restricted cash	15	(22)
Proceeds from the termination of LILO transactions		200
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(2,759)	(2,659)	(2,523)
FINANCING ACTIVITIES
Net issuance/(payment) of short-term debt	(651)	912	539
Issuance of long-term debt	1,850	919	400
Retirement of long-term debt	(480)us-gaap_RepaymentsOfLongTermDebt	(709)us-gaap_RepaymentsOfLongTermDebt	(305)us-gaap_RepaymentsOfLongTermDebt
Debt issuance costs	(17)us-gaap_PaymentsOfDebtIssuanceCosts	(6)us-gaap_PaymentsOfDebtIssuanceCosts	(4)us-gaap_PaymentsOfDebtIssuanceCosts
Common stock dividends	(739)us-gaap_PaymentsOfDividendsCommonStock	(721)us-gaap_PaymentsOfDividendsCommonStock	(709)us-gaap_PaymentsOfDividendsCommonStock
Issuance of common shares for stock plans, net of repurchases	(10)	(8)	(9)
Preferred stock dividends			(3)
Preferred stock redemption			(239)
NET CASH FLOWS (USED IN)/FROM FINANCING ACTIVITIES	(47)	387	(330)
CASH AND TEMPORARY CASH INVESTMENTS:
NET CHANGE FOR THE PERIOD	25	280	(254)
BALANCE AT BEGINNING OF PERIOD	674	394	648
BALANCE AT END OF PERIOD	699	674	394
Cash paid during the period for:
Interest	561us-gaap_InterestPaid	574us-gaap_InterestPaid	571us-gaap_InterestPaid
Income taxes	633us-gaap_IncomeTaxesPaid	69us-gaap_IncomeTaxesPaid	46us-gaap_IncomeTaxesPaid
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	179	174	254
CECONY [Member]
OPERATING ACTIVITIES
NET INCOME	1,058	1,020	1,017
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	991	946	894
Deferred income taxes	331	222	365
Rate case amortization and accruals	102	10	42
Common equity component of allowance for funds used during construction	(1)	(2)	(2)
Other non-cash items (net)	(33)	(80)	14
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers, less allowance for uncollectibles	59	(15)	(131)
Materials and supplies, including fuel oil and gas in storage	(12)	(15)	23
Other receivables and other current assets	35	(88)	(40)
Prepayments	(24)	(21)	4
Accounts payable	(79)	(58)	102
Pensions and retiree benefits obligations (net)	742	803	837
Pensions and retiree benefits contributions	(544)	(830)	(804)
Accrued taxes	(403)	207	94
Accrued interest	(22)	6
Superfund and environmental remediation costs (net)	32	(4)	9
Deferred charges, noncurrent assets and other regulatory assets	(334)	(148)	(239)
Deferred credits and other regulatory liabilities	475	666	100
Other current and noncurrent liabilities	57	24	61
Net Cash Flows from Operating Activities	2,430	2,643	2,346
INVESTING ACTIVITIES
Utility construction expenditures	(2,094)	(2,207)	(1,788)
Cost of removal less salvage	(210)	(210)	(170)
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(2,304)	(2,417)	(1,958)
FINANCING ACTIVITIES
Net issuance/(payment) of short-term debt	(760)	789	421
Issuance of long-term debt	1,850	700	400
Retirement of long-term debt	(475)	(700)	(300)
Debt issuance costs	(17)	(7)	(4)
Dividend to parent	(712)	(728)	(682)
Preferred stock dividends			(3)
Preferred stock redemption			(239)
NET CASH FLOWS (USED IN)/FROM FINANCING ACTIVITIES	(114)	54	(407)
CASH AND TEMPORARY CASH INVESTMENTS:
NET CHANGE FOR THE PERIOD	12	280	(19)
BALANCE AT BEGINNING OF PERIOD	633	353	372
BALANCE AT END OF PERIOD	645	633	353
Cash paid during the period for:
Interest	504	500	513
Income taxes	748	163	62
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	$ 151	$ 116	$ 201

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Future cash outflow to pay for construction in progress expenditures that have occurred.

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