Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 5,231	$ 4,887
Total revenues	5,095	4,798
Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	(136)	(89)
CECONY
Disaggregation of Revenue [Line Items]
Total revenues	4,654	4,441
Operating Segments | Con Edison Transmission
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1	1
Total revenues	1	1
Operating Segments | Con Edison Transmission | Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Operating Segments | CECONY
Disaggregation of Revenue [Line Items]
Total revenues	4,654	4,441
Operating Segments | CECONY | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,757	4,521
Total revenues	4,654	4,441
Operating Segments | CECONY | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(103)	(80)
Operating Segments | CECONY | Electric
Disaggregation of Revenue [Line Items]
Total revenues	2,758	2,686
Operating Segments | CECONY | Electric | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,870	2,768
Total revenues	2,758	2,686
Operating Segments | CECONY | Electric | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(112)	(82)
Operating Segments | CECONY | Gas
Disaggregation of Revenue [Line Items]
Total revenues	1,464	1,401
Operating Segments | CECONY | Gas | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,453	1,398
Total revenues	1,464	1,401
Operating Segments | CECONY | Gas | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	11	3
Operating Segments | CECONY | Steam
Disaggregation of Revenue [Line Items]
Total revenues	432	354
Operating Segments | CECONY | Steam | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	434	355
Total revenues	432	354
Operating Segments | CECONY | Steam | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(2)	(1)
Operating Segments | O&R
Disaggregation of Revenue [Line Items]
Total revenues	441	356
Operating Segments | O&R | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	473	365
Total revenues	441	356
Operating Segments | O&R | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(32)	(9)
Operating Segments | O&R | Electric
Disaggregation of Revenue [Line Items]
Total revenues	282	215
Operating Segments | O&R | Electric | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	289	218
Total revenues	282	215
Operating Segments | O&R | Electric | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(7)	(3)
Operating Segments | O&R | Gas
Disaggregation of Revenue [Line Items]
Total revenues	159	141
Operating Segments | O&R | Gas | Subsidiaries
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	184	147
Total revenues	159	141
Operating Segments | O&R | Gas | Other revenues | Subsidiaries
Disaggregation of Revenue [Line Items]
Total revenues	(25)	(6)
Segment Reporting, Reconciling Item, Corporate Nonsegment
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Total revenues	(1)	0
Segment Reporting, Reconciling Item, Corporate Nonsegment | Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ (1)	$ 0