Shareholders' Equity - Schedule of Common Stock Warrants (Details) - Commonwealth Edison Co [Member] - shares	Dec. 31, 2020	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	60,143	60,228
Common Stock [Member]
Class of Warrant or Right [Line Items]
Common Stock Shares Reserved For Warrant Conversion	20,048	20,076