Consolidated Statement of Changes in Shareholders Equity - ComEd - USD ($) $ in Millions	Total	Retained Earnings	Commonwealth Edison Co	Commonwealth Edison Co Common Stock	Commonwealth Edison Co Other Additional Capital [Member]	Commonwealth Edison Co Retained Earnings
Beginning Balance at Dec. 31, 2020			$ 11,329	$ 1,588	$ 8,285	$ 1,456
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 1,829	$ 1,706	742			742
Common stock dividends	(1,499)	(1,499)	(507)			(507)
Contributions from parent			791		791
Ending Balance at Dec. 31, 2021			12,355	1,588	9,076	1,691
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,171	2,170	917			917
Common stock dividends	(1,336)	(1,336)	(578)			(578)
Contributions from parent			670		670
Ending Balance at Dec. 31, 2022	24,744		13,364	1,588	9,746	2,030
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,328	2,328	1,090			1,090
Common stock dividends	(1,435)	$ (1,435)	(746)			(746)
Contributions from parent			655		655
Ending Balance at Dec. 31, 2023	$ 25,755		$ 14,363	$ 1,588	$ 10,401	$ 2,374