Dispositions	3 Months Ended
	Mar. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Dispositions	DispositionsIn April 2021, a subsidiary of the Clean Energy Businesses entered into an agreement to sell substantially all of its membership interests in a renewable electric project that it developed and also all of its membership interests in a renewable electric project that it acquired in 2016. The sales were completed in June 2021. The combined carrying value of both projects was approximately $192 million in June 2021. The net pre-tax gain on the sales was $3 million ($2 million after-tax) and was included within "Other operations and maintenance" on Con Edison's consolidated income statement for the year ended December 31, 2021. The retained portion of the membership interest in the renewable electric project, of $11 million, was calculated based on a discounted cash flow of future projected earnings, and the retained portion is accounted for as an equity method investment. The portion of the gain attributable to the retained portion of the membership interest was not material for the year ended December 31, 2021.