CONSOLIDATED STATEMENT OF SHAREHOLDER’S 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, 2021			354	235
Beginning Balance at Dec. 31, 2021		$ 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 Con Edison	$ (280)	(245)				$ (280)	(245)
Capital contribution by Con Edison		75			75
Other comprehensive income (loss)		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		16,312		$ 589	7,269		9,478	(962)	(62)		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	857	645
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
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	255	170					170
Common stock dividend to Con Edison	(280)	(245)				(280)	(245)
Capital contribution by Con Edison		25			25
Other comprehensive income (loss)	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
Beginning balance (shares) at Dec. 31, 2022			355	235
Beginning Balance at Dec. 31, 2022	20,687	16,878		$ 589	7,419		9,890	(962)	(62)		4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		604					604
Common stock dividend to Con Edison	(288)	(264)				(288)	(264)
Capital contribution by Con Edison		1,675			1,675
Other comprehensive income (loss)	4	(1)								4	(1)
Ending balance (shares) at Mar. 31, 2023			346	235
Ending Balance at Mar. 31, 2023		18,892		$ 589	9,094		10,230	(962)	(62)		3
Beginning balance (shares) at Dec. 31, 2022			355	235
Beginning Balance at Dec. 31, 2022	20,687	16,878		$ 589	7,419		9,890	(962)	(62)		4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,658	793
Ending balance (shares) at Jun. 30, 2023			344	235
Ending Balance at Jun. 30, 2023	20,805	18,843		$ 589	9,120		10,155	(962)	(62)		3
Beginning balance (shares) at Mar. 31, 2023			346	235
Beginning Balance at Mar. 31, 2023		18,892		$ 589	9,094		10,230	(962)	(62)		3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	226	189					189
Common stock dividend to Con Edison	(281)	(264)				$ (281)	(264)
Capital contribution by Con Edison		26			26
Other comprehensive income (loss)	(1)									$ (1)
Ending balance (shares) at Jun. 30, 2023			344	235
Ending Balance at Jun. 30, 2023	$ 20,805	$ 18,843		$ 589	$ 9,120		$ 10,155	$ (962)	$ (62)		$ 3