CONSOLIDATED STATEMENT OF EQUITY (UNAUDITED) - CECONY - USD ($) shares in Millions, $ in Millions	Total	Subsidiaries	Common Stock	Common Stock Subsidiaries	Additional Paid-In Capital Subsidiaries	Retained Earnings	Retained Earnings Subsidiaries	Repurchased Con Edison Stock Subsidiaries	Capital Stock Expense Subsidiaries	Accumulated Other Comprehensive Income/(Loss)	Accumulated Other Comprehensive Income/(Loss) Subsidiaries
Beginning balance (shares) at Dec. 31, 2020			342	235
Beginning Balance at Dec. 31, 2020		$ 14,849		$ 589	$ 6,169		$ 9,122	$ (962)	$ (62)		$ (7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		465					465
Common stock dividend to parent	$ (265)	(247)				$ (265)	(247)
Capital contribution by parent		125			125
Other comprehensive income	4									$ 4
Ending balance (shares) at Mar. 31, 2021			342	235
Ending Balance at Mar. 31, 2021		15,192		$ 589	6,294		9,340	(962)	(62)		(7)
Beginning balance (shares) at Dec. 31, 2020			342	235
Beginning Balance at Dec. 31, 2020		14,849		$ 589	6,169		9,122	(962)	(62)		(7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,122	1,011
Other comprehensive income	8
Ending balance (shares) at Sep. 30, 2021			354	235
Ending Balance at Sep. 30, 2021		16,220		$ 589	7,270		9,392	(962)	(62)		(7)
Beginning balance (shares) at Mar. 31, 2021			342	235
Beginning Balance at Mar. 31, 2021		15,192		$ 589	6,294		9,340	(962)	(62)		(7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		128					128
Common stock dividend to parent	(266)	(247)				(266)	(247)
Capital contribution by parent		851			851
Other comprehensive income	2									2
Ending balance (shares) at Jun. 30, 2021			353	235
Ending Balance at Jun. 30, 2021		15,924		$ 589	7,145		9,221	(962)	(62)		(7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	538	418					418
Common stock dividend to parent	(274)	(247)				(274)	(247)
Capital contribution by parent		125			125
Other comprehensive income	2									2
Ending balance (shares) at Sep. 30, 2021			354	235
Ending Balance at Sep. 30, 2021		16,220		$ 589	7,270		9,392	(962)	(62)		(7)
Beginning balance (shares) at Dec. 31, 2021			354	235
Beginning Balance at Dec. 31, 2021	20,037	16,312		$ 589	7,269		9,478	(962)	(62)		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		475					475
Common stock dividend to parent	(280)	(245)				(280)	(245)
Capital contribution by parent		75			75
Other comprehensive income		1									1
Ending balance (shares) at Mar. 31, 2022			354	235
Ending Balance at Mar. 31, 2022		16,618		$ 589	7,344		9,708	(962)	(62)		1
Beginning balance (shares) at Dec. 31, 2021			354	235
Beginning Balance at Dec. 31, 2021	20,037	16,312		$ 589	7,269		9,478	(962)	(62)		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,470	1,138
Other comprehensive income	6
Ending balance (shares) at Sep. 30, 2022			355	235
Ending Balance at Sep. 30, 2022	20,748	16,867		$ 589	7,419		9,882	(962)	(62)		1
Beginning balance (shares) at Mar. 31, 2022			354	235
Beginning Balance at Mar. 31, 2022		16,618		$ 589	7,344		9,708	(962)	(62)		1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		170					170
Common stock dividend to parent	(280)	(245)				(280)	(245)
Capital contribution by parent		25			25
Other comprehensive income	5									5
Ending balance (shares) at Jun. 30, 2022			354	235
Ending Balance at Jun. 30, 2022		16,568		$ 589	7,369		9,633	(962)	(62)		1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	613	493					493
Common stock dividend to parent	(280)	(244)				$ (280)	(244)
Capital contribution by parent		50			50
Other comprehensive income	1									$ 1
Ending balance (shares) at Sep. 30, 2022			355	235
Ending Balance at Sep. 30, 2022	$ 20,748	$ 16,867		$ 589	$ 7,419		$ 9,882	$ (962)	$ (62)		$ 1