Pension Benefits - Schedule of Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	$ 525
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	459	$ 525
Pension Benefits
CHANGE IN PROJECTED BENEFIT OBLIGATION
Projected benefit obligation at beginning of year	17,357	18,965	$ 16,792
Service cost – excluding administrative expenses	283	337	288
Interest cost on projected benefit obligation	505	471	549
Net actuarial loss/(gain)	(5,102)	(1,547)	2,281
Benefits paid	(930)	(869)	(945)
PROJECTED BENEFIT OBLIGATION AT END OF YEAR	12,113	17,357	18,965
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	18,504	17,022	15,608
Actual return on plan assets	(2,583)	1,935	1,927
Employer contributions	30	469	475
Benefits paid	(930)	(869)	(945)
Administrative expenses	(42)	(53)	(43)
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	14,979	18,504	17,022
FUNDED STATUS	2,866	1,147	(1,943)
Unrecognized net loss/(gain)	(1,485)	205	3,330
Unrecognized prior service costs/(credits)	(124)	(140)	(156)
Accumulated benefit obligation	11,167	15,469	16,768
CECONY
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	499
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	439	499
CECONY | Pension Benefits
CHANGE IN PROJECTED BENEFIT OBLIGATION
Projected benefit obligation at beginning of year	16,341	17,821	15,750
Service cost – excluding administrative expenses	266	317	269
Interest cost on projected benefit obligation	475	443	515
Net actuarial loss/(gain)	(4,845)	(1,441)	2,154
Benefits paid	(842)	(799)	(867)
PROJECTED BENEFIT OBLIGATION AT END OF YEAR	11,395	16,341	17,821
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	17,566	16,147	14,790
Actual return on plan assets	(2,453)	1,838	1,830
Employer contributions	17	432	435
Benefits paid	(842)	(799)	(867)
Administrative expenses	(40)	(52)	(41)
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	14,248	17,566	16,147
FUNDED STATUS	2,853	1,225	(1,674)
Unrecognized net loss/(gain)	(1,397)	207	3,145
Unrecognized prior service costs/(credits)	(143)	(163)	(183)
Accumulated benefit obligation	$ 10,478	$ 14,504	$ 15,676