Schedule I - Condensed Financial Information - Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Cash Flow Statements, Captions [Line Items]
Net Income		$ 1,660	$ 1,346	$ 1,101
Deferred income taxes	$ 121	435	133	85
Change in Assets and Liabilities:
Other – net (b)		31	(234)	(179)
NET CASH FLOWS FROM OPERATING ACTIVITIES		3,935	2,733	2,198
INVESTING ACTIVITIES
NET CASH FLOWS USED IN INVESTING ACTIVITIES		(4,565)	(3,484)	(4,224)
FINANCING ACTIVITIES
Net proceeds of short-term debt		1,702	(382)	178
Issuance of long-term debt		800	2,804	2,925
Retirement of long-term debt		(406)	(1,960)	(518)
Debt issuance costs		(13)	(40)	(47)
Issuance of common shares for stock plans		57	60	58
Issuance of common shares - public offering		0	775	640
Common stock dividends		(1,089)	(1,030)	(975)
NET CASH FLOWS FROM FINANCING ACTIVITIES		1,014	461	2,245
NET CHANGE FOR THE PERIOD		384	(290)	219
BALANCE AT BEGINNING OF PERIOD		1,146	1,436	1,217
BALANCE AT END OF PERIOD	1,530	1,530	1,146	1,436
CECONY
Condensed Cash Flow Statements, Captions [Line Items]
Net Income		1,390	1,344	1,185
Deferred income taxes		85	124	168
Change in Assets and Liabilities:
Accounts receivable from affiliated companies		8	(96)	61
Accrued taxes to affiliated companies		79	9	1
Accounts payable to affiliated companies		(1)	(4)	9
Other – net (b)		56	(354)	(98)
NET CASH FLOWS FROM OPERATING ACTIVITIES		3,263	2,186	1,693
INVESTING ACTIVITIES
NET CASH FLOWS USED IN INVESTING ACTIVITIES		(3,926)	(3,729)	(3,416)
FINANCING ACTIVITIES
Net proceeds of short-term debt		939	(299)	523
Issuance of long-term debt		700	2,250	2,200
Retirement of long-term debt		0	(640)	(350)
Debt issuance costs		(12)	(27)	(34)
NET CASH FLOWS FROM FINANCING ACTIVITIES		799	1,396	1,857
NET CHANGE FOR THE PERIOD		136	(147)	134
BALANCE AT BEGINNING OF PERIOD		920	1,067	933
BALANCE AT END OF PERIOD	1,056	1,056	920	1,067
Parent Company
Condensed Cash Flow Statements, Captions [Line Items]
Net Income		1,660	1,346	1,101
Equity in earnings of subsidiaries		(1,860)	(1,369)	(1,105)
Deferred income taxes		163	119	32
Change in Assets and Liabilities:
Accounts receivable from affiliated companies		(138)	57	(386)
Accrued taxes to affiliated companies		(1)	(1)	(78)
Accounts payable to affiliated companies		1	1	0
Other – net (b)		56	50	(89)
NET CASH FLOWS FROM OPERATING ACTIVITIES		1,015	1,459	538
INVESTING ACTIVITIES
Contributions to subsidiaries		(150)	(1,135)	(626)
Debt receivable from affiliated companies		0	875	400
NET CASH FLOWS USED IN INVESTING ACTIVITIES		(150)	(260)	(226)
FINANCING ACTIVITIES
Net proceeds of short-term debt		632	50	(537)
Issuance of long-term debt		0	0	650
Retirement of long-term debt		(293)	(1,178)	(3)
Debt issuance costs		0	(1)	(3)
Issuance of common shares for stock plans		57	60	58
Issuance of common shares - public offering		0	775	640
Common stock dividends		(1,089)	(1,030)	(975)
NET CASH FLOWS FROM FINANCING ACTIVITIES		(693)	(1,324)	(170)
NET CHANGE FOR THE PERIOD		172	(125)	142
BALANCE AT BEGINNING OF PERIOD		19	144	2
BALANCE AT END OF PERIOD	$ 191	191	19	144
Parent Company | Revision of Prior Period, Adjustment
FINANCING ACTIVITIES
Retirement of long-term debt			(1,175)
Parent Company | CECONY
Condensed Cash Flow Statements, Captions [Line Items]
Dividends received		978	988	982
Parent Company | O&R
Condensed Cash Flow Statements, Captions [Line Items]
Dividends received		57	52	49
Parent Company | Clean Energy Businesses
Condensed Cash Flow Statements, Captions [Line Items]
Dividends received		98	64	21
Parent Company | Con Edison Transmission
Condensed Cash Flow Statements, Captions [Line Items]
Dividends received		$ 1	$ 152	$ 11