Regulatory Matters - Schedule of Pending Rate Cases (Details) - USD ($) $ in Millions	Jan. 26, 2024	Sep. 29, 2023	Apr. 13, 2023
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			$ 191
Public Utilities, Requested Return on Equity, Percentage			10.50%
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case | 2024
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			$ 117
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case | 2025
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			37
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case | 2026
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			$ 37
Potomac Electric Power Company | Pepco Maryland 2023 Electric Distribution Base Rate Case | Forecast
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 188
Public Utilities, Requested Return on Equity, Percentage	10.50%
Potomac Electric Power Company | Pepco Maryland 2023 Electric Distribution Base Rate Case | Forecast | 2024
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 69
Potomac Electric Power Company | Pepco Maryland 2023 Electric Distribution Base Rate Case | Forecast | 2025
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	54
Potomac Electric Power Company | Pepco Maryland 2023 Electric Distribution Base Rate Case | Forecast | 2026
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	51
Potomac Electric Power Company | Pepco Maryland 2023 Electric Distribution Base Rate Case | Forecast | 2027
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 14
Delmarva Power & Light Company | Delaware 2022 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 39
Public Utilities, Requested Return on Equity, Percentage		10.50%