Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Retained earnings/Undistributed earnings (losses)	$ 4,502						$ 4,502		$ 16,942
Deferred income taxes and unamortized investment tax credits	11,113						11,113		10,611
Net income (loss)	676	$ 465	$ 598	$ 1,229	$ 476	$ (264)	1,739	$ 1,441
Atlantic City Electric Company [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Retained earnings/Undistributed earnings (losses)	(12)						(12)		(15)
Deferred income taxes and unamortized investment tax credits	733						733		682
Net income (loss)	94	11	26	90	37	14	131	141
Pepco Holdings LLC [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Retained earnings/Undistributed earnings (losses)	(316)						(316)		(210)
Deferred income taxes and unamortized investment tax credits	2,864						2,864		$ 2,675
Net income (loss)	$ 289	$ 100	$ 130	$ 266	$ 141	$ 128	$ 518	$ 535