Stock-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum employer contribution match (up to)	$ 1
Amount employee contribution for employer match	9
Maximum employee investment per year (up to)	$ 25,000
Maximum percentage allowed to invest (not more than) (in percent)	20.00%
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock received upon vesting (in shares)	1
Compensation expense to be recognized	$ 29,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
Payment for settlement of vested units	$ 22,000,000	$ 30,000,000	$ 21,000,000
Performance RSUs | CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense to be recognized	$ 26,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
Payment for settlement of vested units	$ 20,000,000	27,000,000	19,000,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Time-based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense to be recognized	$ 22,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
Payment for settlement of vested units	$ 3,000,000	2,000,000	2,000,000
Weighted average grant date price per share (in dollars per share)	$ 98.27
Time-based Awards | CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense to be recognized	$ 20,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
Payment for settlement of vested units	$ 3,000,000	$ 2,000,000	$ 2,000,000
Weighted average grant date price per share (in dollars per share)	$ 99.80
2013 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock that can be awarded under the plan (in shares)	10,000,000
TSR Portion | Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards (in percent)	50.00%
Factor used for adjustment of Performance awards, low end (percent)	0.00%
Factor used for adjustment of Performance awards, high end (in percent)	200.00%
Weighted average grant date price per share (in dollars per share)	$ 107.68
TSR Portion | Performance RSUs | CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date price per share (in dollars per share)	$ 108.99
Non-TSR Portion | Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards (in percent)	50.00%
Factor used for adjustment of Performance awards, low end (percent)	0.00%
Factor used for adjustment of Performance awards, high end (in percent)	200.00%
Weighted average grant date price per share (in dollars per share)	$ 99.30
Non-TSR Portion | Performance RSUs | CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date price per share (in dollars per share)	$ 100.04
LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units issued (in shares)	26,656
Weighted average grant date price per share (in dollars per share)	$ 103.26
Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased on the open market (in shares)	757,757	774,338	751,702
Weighted average share price per share, on shares purchased on open market (in dollars per share)	$ 100.46	$ 94.71	$ 91.80