Regulatory Matters - Schedule of Pending Rate Cases (Details) - USD ($) $ in Millions	Sep. 20, 2024	Sep. 11, 2024	Aug. 30, 2024	Aug. 13, 2024	Mar. 28, 2024	Feb. 27, 2024
Commonwealth Edison Co | Illinois 2024 Refiled Grid Plan
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended				$ 667
Requested Return on Equity, Percentage				8.905%
Commonwealth Edison Co | Illinois 2024 Refiled Grid Plan | 2024
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended				$ 309
Commonwealth Edison Co | Illinois 2024 Refiled Grid Plan | 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended				95
Commonwealth Edison Co | Illinois 2024 Refiled Grid Plan | 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended				128
Commonwealth Edison Co | Illinois 2024 Refiled Grid Plan | 2027
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended				$ 135
Commonwealth Edison Co | Illinois 2024 Electric Distribution Reconciliation Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation		$ 624
Requested Return on Equity, Percentage		9.89%
PECO Energy Co | Pennsylvania 2024 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)			$ 354		$ 464
Requested Return on Equity, Percentage					10.95%
PECO Energy Co | Pennsylvania 2024 Electric Distribution Base Rate Case | 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)					$ (64)
PECO Energy Co | Pennsylvania 2023 Natural Gas Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)					$ 111
Requested Return on Equity, Percentage					11.15%
PECO Energy Co | Pennsylvania 2024 Gas Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)			$ 78
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended						$ 186
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]
Requested Revenue Requirement Increase (Decrease)						$ 116
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case | 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)						35
Potomac Electric Power Company | District of Columbia 2023 Electric Distribution Base Rate Case | 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)						$ 35
Delmarva Power and Light Company | DPL 2024 Natural Gas Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)	$ 36
Requested Return on Equity, Percentage	10.65%