Pension Benefits - Schedule of Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	$ 583
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	620	$ 583
Pension Benefits
CHANGE IN PROJECTED BENEFIT OBLIGATION
Projected benefit obligation at beginning of year	12,141	12,712	$ 12,113
Service cost – excluding administrative expenses	162	172	156
Interest cost on projected benefit obligation	675	642	649
Net actuarial loss (gain)	422	(557)	599
Plan amendments	0	0	3
Benefits paid	(883)	(828)	(808)
PROJECTED BENEFIT OBLIGATION AT END OF YEAR	12,517	12,141	12,712
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	15,278	15,404	14,979
Actual return on plan assets	1,642	724	1,261
Employer contributions	56	20	21
Benefits paid	(883)	(828)	(808)
Administrative expenses	(41)	(42)	(49)
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	16,052	15,278	15,404
FUNDED STATUS	3,535	3,137	2,692
Unrecognized net gain	(673)	(857)	(757)
Unrecognized prior service credits	(71)	(88)	(105)
Accumulated benefit obligation	11,478	11,236	11,739
CECONY
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	560
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	598	560
CECONY | Pension Benefits
CHANGE IN PROJECTED BENEFIT OBLIGATION
Projected benefit obligation at beginning of year	11,435	11,977	11,395
Service cost – excluding administrative expenses	153	162	146
Interest cost on projected benefit obligation	636	604	611
Net actuarial loss (gain)	391	(557)	572
Plan amendments	0	0	0
Benefits paid	(813)	(751)	(747)
PROJECTED BENEFIT OBLIGATION AT END OF YEAR	11,802	11,435	11,977
CHANGE IN PLAN ASSETS
Fair value of plan assets at beginning of year	14,591	14,674	14,248
Actual return on plan assets	1,570	691	1,201
Employer contributions	53	17	18
Benefits paid	(813)	(751)	(747)
Administrative expenses	(40)	(40)	(46)
FAIR VALUE OF PLAN ASSETS AT END OF YEAR	15,361	14,591	14,674
FUNDED STATUS	3,559	3,156	2,697
Unrecognized net gain	(663)	(825)	(705)
Unrecognized prior service credits	(84)	(104)	(124)
Accumulated benefit obligation	$ 10,778	$ 10,554	$ 11,031