Income Taxes - Schedule of Carryforwards and Corresponding Valuation Allowances (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 369	$ 264
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	6,349
Deferred taxes on state tax attributes (net of federal taxes)	369
Valuation allowance on state tax attributes (net of federal taxes)	$ 86
Operating loss carryforwards, expiration date	Dec. 31, 2035
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 369
Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	142
Commonwealth Edison Co
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	47	118
Commonwealth Edison Co | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	0
Deferred taxes on state tax attributes (net of federal taxes)	0
Valuation allowance on state tax attributes (net of federal taxes)	0
Commonwealth Edison Co | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	47
Commonwealth Edison Co | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
PECO Energy Co
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	166	82
PECO Energy Co | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	1,711
Deferred taxes on state tax attributes (net of federal taxes)	67
Valuation allowance on state tax attributes (net of federal taxes)	$ 4
Operating loss carryforwards, expiration date	Dec. 31, 2031
PECO Energy Co | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 166
PECO Energy Co | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
Baltimore Gas and Electric Company
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	95	55
Baltimore Gas and Electric Company | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	1,204
Deferred taxes on state tax attributes (net of federal taxes)	78
Valuation allowance on state tax attributes (net of federal taxes)	$ 0
Operating loss carryforwards, expiration date	Dec. 31, 2033
Baltimore Gas and Electric Company | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 95
Baltimore Gas and Electric Company | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
Pepco Holdings LLC
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	2	0
Pepco Holdings LLC | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	1,392
Deferred taxes on state tax attributes (net of federal taxes)	97
Valuation allowance on state tax attributes (net of federal taxes)	29
Pepco Holdings LLC | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	2
Pepco Holdings LLC | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
Potomac Electric Power Company
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	2	0
Potomac Electric Power Company | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	0
Deferred taxes on state tax attributes (net of federal taxes)	0
Valuation allowance on state tax attributes (net of federal taxes)	0
Potomac Electric Power Company | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	2
Potomac Electric Power Company | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
Delmarva Power & Light Company
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	4	2
Delmarva Power & Light Company | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	670
Deferred taxes on state tax attributes (net of federal taxes)	45
Valuation allowance on state tax attributes (net of federal taxes)	$ 29
Operating loss carryforwards, expiration date	Dec. 31, 2033
Delmarva Power & Light Company | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 4
Delmarva Power & Light Company | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	0
Atlantic City Electric Company
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	8	$ 11
Atlantic City Electric Company | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	722
Deferred taxes on state tax attributes (net of federal taxes)	51
Valuation allowance on state tax attributes (net of federal taxes)	$ 0
Operating loss carryforwards, expiration date	Dec. 31, 2031
Atlantic City Electric Company | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Corporate Alternative Minimum Tax	$ 8
Atlantic City Electric Company | Domestic Tax Authority | General Business Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Federal general business credits carryforwards	$ 0