Revenue Recognition - Additional information (Details) - CECONY - NYSPSC - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Electric
Disaggregation of Revenue [Line Items]
Amount of cost recovery	$ 43	$ 19	$ 43
Gas
Disaggregation of Revenue [Line Items]
Amount of cost recovery	$ 7	$ 4	$ 7

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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