Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 15,455	$ 13,456	$ 12,026
Revenues	15,670	13,676	12,246
Other
Disaggregation of Revenue [Line Items]
Revenues	215	220	220
CECONY
Disaggregation of Revenue [Line Items]
Revenues	13,268	11,716	10,647
CECONY | Decoupling Mechanisms
Disaggregation of Revenue [Line Items]
Revenues		48
CECONY | EAMs
Disaggregation of Revenue [Line Items]
Revenues		34
CECONY | LPCs
Disaggregation of Revenue [Line Items]
Revenues		74
O&R | Decoupling Mechanisms
Disaggregation of Revenue [Line Items]
Revenues		(18)
O&R | EAMs
Disaggregation of Revenue [Line Items]
Revenues		2
O&R | LPCs
Disaggregation of Revenue [Line Items]
Revenues		4
Operating Segments | Clean Energy Businesses
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	998	917	661
Revenues	1,319	1,022	736
Operating Segments | Clean Energy Businesses | Other
Disaggregation of Revenue [Line Items]
Revenues	321	105	75
Operating Segments | Clean Energy Businesses | Renewables
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	637	638	608
Revenues	637	638	608
Operating Segments | Clean Energy Businesses | Renewables | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Operating Segments | Clean Energy Businesses | Energy services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	317	234	52
Revenues	317	234	52
Operating Segments | Clean Energy Businesses | Energy services | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Operating Segments | Clean Energy Businesses | Develop/Transfer Projects
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	44	45	1
Revenues	44	45	1
Operating Segments | Clean Energy Businesses | Develop/Transfer Projects | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Operating Segments | Clean Energy Businesses | Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0
Revenues	321	105	75
Operating Segments | Clean Energy Businesses | Other | Other
Disaggregation of Revenue [Line Items]
Revenues	321	105	75
Operating Segments | Con Edison Transmission
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4	4	4
Revenues	4	4	4
Operating Segments | Con Edison Transmission | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Operating Segments | CECONY
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	13,376	11,579	10,518
Revenues	13,268	11,716	10,647
Operating Segments | CECONY | Other
Disaggregation of Revenue [Line Items]
Revenues	(108)	137	129
Operating Segments | CECONY | Electric
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,917	8,736	8,026
Revenues	9,751	8,806	8,103
Operating Segments | CECONY | Electric | Other
Disaggregation of Revenue [Line Items]
Revenues	(166)	70	77
Operating Segments | CECONY | Gas
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,875	2,324	1,998
Revenues	2,924	2,378	2,036
Operating Segments | CECONY | Gas | Other
Disaggregation of Revenue [Line Items]
Revenues	49	54	38
Operating Segments | CECONY | Steam
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	584	519	494
Revenues	593	532	508
Operating Segments | CECONY | Steam | Other
Disaggregation of Revenue [Line Items]
Revenues	9	13	14
Operating Segments | O&R
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,077	956	843
Revenues	1,085	941	862
Operating Segments | O&R | Other
Disaggregation of Revenue [Line Items]
Revenues	8	(15)	19
Operating Segments | O&R | Electric
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	771	691	619
Revenues	773	681	629
Operating Segments | O&R | Electric | Other
Disaggregation of Revenue [Line Items]
Revenues	2	(10)	10
Operating Segments | O&R | Gas
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	306	265	224
Revenues	312	260	233
Operating Segments | O&R | Gas | Other
Disaggregation of Revenue [Line Items]
Revenues	6	(5)	9
Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0
Revenues	(6)	(7)	(3)
Other | Other
Disaggregation of Revenue [Line Items]
Revenues	(6)	(7)	(3)
Other | O&R
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 0	$ 0