Regulatory Matters - Schedule of Pending Rate Cases (Details) - USD ($) $ in Millions				12 Months Ended
	Dec. 05, 2019	Sep. 16, 2019	May 16, 2019	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Potomac Electric Power Company [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount							$ 26
Public Utilities, Requested Rate Increase (Decrease), Amount							15
Potomac Electric Power Company [Member] | Electric Distribution [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount			$ 27
Delmarva Power & Light Company [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount							16
Public Utilities, Requested Rate Increase (Decrease), Amount							$ 17
Delmarva Power & Light Company [Member] | Electric Distribution [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 19
Public Utilities, Requested Return on Equity, Percentage	10.30%
DISTRICT OF COLUMBIA | Potomac Electric Power Company [Member] | Electric Distribution [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 160
Public Utilities, Requested Return on Equity, Percentage		10.30%
Forecast [Member] | DISTRICT OF COLUMBIA | Potomac Electric Power Company [Member] | Electric Distribution [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount				$ 36	$ 40	$ 84