Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 15,469	$ 14,476	$ 15,455
TOTAL OPERATING REVENUES	15,256	14,663	15,670
Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(213)	187	215
CECONY
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	14,129	13,476	13,268
Operating Segments | Clean Energy Businesses
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	82	998
TOTAL OPERATING REVENUES	0	129	1,319
Operating Segments | Clean Energy Businesses | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	47	321
Operating Segments | Clean Energy Businesses | Renewables
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	68	637
TOTAL OPERATING REVENUES	0	68	637
Operating Segments | Clean Energy Businesses | Renewables | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	0	0
Operating Segments | Clean Energy Businesses | Energy services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	7	317
TOTAL OPERATING REVENUES	0	7	317
Operating Segments | Clean Energy Businesses | Energy services | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	0	0
Operating Segments | Clean Energy Businesses | Develop/Transfer Projects
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	7	44
TOTAL OPERATING REVENUES	0	7	44
Operating Segments | Clean Energy Businesses | Develop/Transfer Projects | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	0	0
Operating Segments | Clean Energy Businesses | Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0
TOTAL OPERATING REVENUES	0	47	321
Operating Segments | Clean Energy Businesses | Other | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	47	321
Operating Segments | Con Edison Transmission
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4	4	4
TOTAL OPERATING REVENUES	4	4	4
Operating Segments | Con Edison Transmission | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	0	0	0
Operating Segments | CECONY
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	14,129	13,476	13,268
Operating Segments | CECONY | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	14,350	13,364	13,376
TOTAL OPERATING REVENUES	14,129	13,476	13,268
Operating Segments | CECONY | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(221)	112	(108)
Operating Segments | CECONY | Electric
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES		10,078	9,751
Operating Segments | CECONY | Electric | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	10,868	9,946	9,917
TOTAL OPERATING REVENUES	10,717	10,078	9,751
Operating Segments | CECONY | Electric | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(151)	132	(166)
Operating Segments | CECONY | Gas
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES		2,829	2,924
Operating Segments | CECONY | Gas | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,890	2,867	2,875
TOTAL OPERATING REVENUES	2,834	2,829	2,924
Operating Segments | CECONY | Gas | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(56)	(38)	49
Operating Segments | CECONY | Steam
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES		569	593
Operating Segments | CECONY | Steam | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	592	551	584
TOTAL OPERATING REVENUES	578	569	593
Operating Segments | CECONY | Steam | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(14)	18	9
Operating Segments | O&R
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	1,125	1,056	1,085
Operating Segments | O&R | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,115	1,026	1,077
TOTAL OPERATING REVENUES	1,125	1,056	1,085
Operating Segments | O&R | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	10	30	8
Operating Segments | O&R | Electric
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES		759	773
Operating Segments | O&R | Electric | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	865	740	771
TOTAL OPERATING REVENUES	852	759	773
Operating Segments | O&R | Electric | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	(13)	19	2
Operating Segments | O&R | Gas
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES		297	312
Operating Segments | O&R | Gas | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	250	286	306
TOTAL OPERATING REVENUES	273	297	312
Operating Segments | O&R | Gas | Other | Subsidiaries
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	23	11	6
Other (b)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0
TOTAL OPERATING REVENUES	(2)	(2)	(6)
Other (b) | Other
Disaggregation of Revenue [Line Items]
TOTAL OPERATING REVENUES	$ (2)	$ (2)	$ (6)