Income Tax - Income Tax Reconciliation (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
STATUTORY TAX RATE
Federal	21.00%	21.00%	21.00%	21.00%
Changes in computed taxes resulting from:
State income tax, net of federal income taxes	1.00%	2.00%	5.00%	4.00%
Amortization of excess deferred federal income taxes	(27.00%)	(17.00%)	(9.00%)	(5.00%)
Cost of removal	4.00%	4.00%	0.00%	1.00%
Other plant-related items	(4.00%)	(1.00%)	(1.00%)	0.00%
Renewable energy credits	0.00%	(1.00%)
Injuries and damages reserve	0.00%	1.00%
Remeasurement of deferred NYS income taxes, net of federal income taxes	0.00%	4.00%	0.00%	1.00%
Research and development credits	0.00%	(1.00%)	0.00%	0.00%
Deferred unamortized ITC recognized on sale of subsidiary			0	(0.06)
Gain on sale of subsidiary			0	(0.02)
Other	0.00%	0.00%
Effective tax rate	(5.00%)	12.00%	16.00%	14.00%
CECONY | Subsidiaries
STATUTORY TAX RATE
Federal	21.00%	21.00%	21.00%	21.00%
Changes in computed taxes resulting from:
State income tax, net of federal income taxes	4.00%	5.00%	5.00%	5.00%
Amortization of excess deferred federal income taxes	(27.00%)	(18.00%)	(9.00%)	(8.00%)
Cost of removal	4.00%	4.00%	2.00%	2.00%
Other plant-related items	(2.00%)	(1.00%)	(1.00%)	(1.00%)
Renewable energy credits	0.00%	0.00%
Injuries and damages reserve	0.00%	1.00%
Remeasurement of deferred NYS income taxes, net of federal income taxes	0.00%	4.00%	0.00%	1.00%
Research and development credits	(1.00%)	(1.00%)	(1.00%)	(1.00%)
Deferred unamortized ITC recognized on sale of subsidiary			0	0
Gain on sale of subsidiary			0	0
Other	1.00%	0.00%
Effective tax rate	0.00%	15.00%	17.00%	19.00%