Revenue Recognition - Additional information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended			13 Months Ended
	Apr. 30, 2022	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2023	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2022	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Remaining performance obligation								$ 303.0
Late fee and other fees not collected		$ 12.0	$ 49.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Disaggregation of Revenue [Line Items]
Remaining performance obligation								$ 265.0
Expected timing of satisfaction								2 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-02
Disaggregation of Revenue [Line Items]
Remaining performance obligation								$ 38.0
Expected timing of satisfaction
CECONY | Subsidiaries
Disaggregation of Revenue [Line Items]
Late fee and other fees not collected		$ 11.0	$ 46.0
CECONY | COVID-19 | Subsidiaries | Scenario, Forecast | Electric
Disaggregation of Revenue [Line Items]
Late payment charges and fees				$ 19.0			$ 43.0
CECONY | COVID-19 | Subsidiaries | Scenario, Forecast | Gas
Disaggregation of Revenue [Line Items]
Late payment charges and fees				$ 4.0			$ 7.0
O&R | Subsidiaries | Electric and Gas Transmission Projects
Disaggregation of Revenue [Line Items]
Rate plan, term	3 years
O&R | COVID-19 | Subsidiaries | Electric
Disaggregation of Revenue [Line Items]
Late payment charges and fees						$ 1.7
O&R | COVID-19 | Subsidiaries | Gas
Disaggregation of Revenue [Line Items]
Late payment charges and fees					$ 2.4