Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OPERATING ACTIVITIES
Net Income	$ 1,440	$ 1,382	$ 1,525
Net income	1,343	1,382	1,525
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	1,684	1,438	1,341
Deferred income taxes	308	408	485
Rate case amortization and accruals	(116)	(117)	(124)
Common equity component of allowance for funds used during construction	(14)	(12)	(11)
Net derivative (gains)/losses	27	8	(4)
(Gain) on Sale of Assets	(14)	0	0
Unbilled revenue and net unbilled revenue deferrals	(3)	18	(113)
(Gain) on sale of retail electric supply business and solar electric production projects	0	0	(1)
(Gain) on existing project interests due to acquisition of Sempra Solar Holdings, LLC	0	(131)	0
Other non-cash items, net	(18)	115	5
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers	23	(140)	9
Materials and supplies, including fuel oil and gas in storage	6	(20)	5
Revenue decoupling mechanism receivable	(76)	0	0
Other receivables and other current assets	54	(62)	0
Taxes receivable	29	27	15
Prepayments	(73)	(7)	(19)
Accounts payable	10	(46)	95
Pensions and retiree benefits obligations, net	357	325	414
Pensions and retiree benefits contributions	(357)	(479)	(467)
Accrued taxes	10	(49)	44
Accrued interest	24	(35)	(7)
Superfund and environmental remediation costs, net	(9)	(19)	(14)
Distributions from equity investments	57	107	108
System benefit charge	20	92	101
Deferred charges, noncurrent assets and other regulatory assets	(492)	(393)	2,376
Deferred credits and other regulatory liabilities	278	436	(2,524)
Other current and noncurrent liabilities	(21)	(151)	128
NET CASH FLOWS FROM OPERATING ACTIVITIES	3,134	2,695	3,367
INVESTING ACTIVITIES
Utility construction expenditures	(3,238)	(3,251)	(3,028)
Cost of removal less salvage	(295)	(258)	(248)
Non-utility construction expenditures	(248)	(246)	(415)
Acquisition of Sempra Solar Holdings, LLC, net of cash acquired	0	(1,488)	0
Proceeds from sale of assets	192	5	34
Other investing activities	22	34	37
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(3,782)	(5,471)	(3,710)
FINANCING ACTIVITIES
Net (payment)/issuance of short-term debt	(874)	1,989	(477)
Issuance of long-term debt	3,017	3,030	1,697
Retirement of long-term debt	(1,195)	(1,938)	(434)
Debt issuance costs	(32)	(61)	(19)
Common stock dividends	(924)	(842)	(803)
Issuance of common shares - public offering	825	705	343
Issuance of common shares for stock plans	54	53	51
Distribution to noncontrolling interest	(12)	2	(1)
NET CASH FLOWS FROM FINANCING ACTIVITIES	859	2,938	357
CASH, TEMPORARY CASH INVESTMENTS AND RESTRICTED CASH:
NET CHANGE FOR THE PERIOD	211	162	14
BALANCE AT BEGINNING OF PERIOD	1,006	844	830
BALANCE AT END OF PERIOD	1,217	1,006	844
Cash paid/(received) during the period for:
Interest	876	805	725
Income taxes	(26)	0	(29)
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	336	369	432
Issuance of common shares for dividend reinvestment	47	47	46
Electric and Gas Transmission Projects
INVESTING ACTIVITIES
Investments in/acquisitions of projects	(205)	(248)	(45)
Renewable Electric Production Projects
INVESTING ACTIVITIES
Investments in/acquisitions of projects	(10)	(19)	(45)
CECONY
OPERATING ACTIVITIES
Net income	1,250	1,196	1,104
PRINCIPAL NON-CASH CHARGES/(CREDITS) TO INCOME
Depreciation and amortization	1,373	1,276	1,195
Deferred income taxes	128	354	575
Rate case amortization and accruals	(117)	(133)	(142)
Common equity component of allowance for funds used during construction	(12)	(11)	(10)
(Gain) on Sale of Assets	(14)	0	0
Unbilled revenue and net unbilled revenue deferrals	(3)	(4)	(17)
Other non-cash items, net	7	13	(59)
CHANGES IN ASSETS AND LIABILITIES
Accounts receivable - customers	3	(153)	15
Materials and supplies, including fuel oil and gas in storage	11	(17)	(17)
Revenue decoupling mechanism receivable	(76)	0	0
Other receivables and other current assets	54	(96)	23
Accounts receivables from affiliated companies	141	(150)	45
Prepayments	(61)	(9)	(8)
Accounts payable	(7)	(27)	125
Accounts payable to affiliated companies	(4)	7	0
Pensions and retiree benefits obligations, net	330	293	370
Pensions and retiree benefits contributions	(325)	(440)	(420)
Accrued taxes	11	(47)	52
Accrued taxes to affiliated companies	0	(72)	(47)
Accrued interest	1	(1)	2
Superfund and environmental remediation costs, net	(12)	(18)	(12)
System benefit charge	18	86	85
Deferred charges, noncurrent assets and other regulatory assets	(486)	(314)	2,212
Deferred credits and other regulatory liabilities	306	549	(2,242)
Other current and noncurrent liabilities	(14)	(78)	37
NET CASH FLOWS FROM OPERATING ACTIVITIES	2,502	2,204	2,866
INVESTING ACTIVITIES
Utility construction expenditures	(3,028)	(3,051)	(2,840)
Cost of removal less salvage	(288)	(255)	(240)
Proceeds from sale of assets	192	0	0
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(3,124)	(3,306)	(3,080)
FINANCING ACTIVITIES
Net (payment)/issuance of short-term debt	(55)	1,042	(450)
Issuance of long-term debt	1,300	2,740	1,200
Retirement of long-term debt	(475)	(1,836)	0
Debt issuance costs	(21)	(30)	(15)
Capital contribution by parent	900	120	301
Dividend to parent	(912)	(846)	(796)
NET CASH FLOWS FROM FINANCING ACTIVITIES	737	1,190	240
CASH, TEMPORARY CASH INVESTMENTS AND RESTRICTED CASH:
NET CHANGE FOR THE PERIOD	115	88	26
BALANCE AT BEGINNING OF PERIOD	818	730	704
BALANCE AT END OF PERIOD	933	818	730
Cash paid/(received) during the period for:
Interest	676	662	602
Income taxes	73	195	108
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Construction expenditures in accounts payable	285	299	351
Software Licenses
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Capital expenditures incurred but unpaid as of end of period	80	100	0
Software Licenses | CECONY
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Capital expenditures incurred but unpaid as of end of period	76	95	0
Equipment
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Capital expenditures incurred but unpaid as of end of period	33	0	0
Equipment | CECONY
SUPPLEMENTAL DISCLOSURE OF NON-CASH INFORMATION
Capital expenditures incurred but unpaid as of end of period	$ 33	$ 0	$ 0