Debt and Credit Agreements - Summary of Outstanding Long-term Debt (Details) - USD ($) $ in Millions	Jan. 24, 2022	Jan. 21, 2022	Jan. 10, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, gross				$ 36,779	$ 32,523
Unamortized debt discount and premium, net				(74)	(70)
Unamortized debt issuance costs				(257)	(220)
Fair value adjustment				626	669
Long-term Debt, Current Maturities				(1,802)	(2,153)
Long-term Debt, Excluding Current Maturities				35,272	30,749
Long-term debt to financing trusts				390	390
Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross				9,489	7,289
Unamortized debt discount and premium, net				10	10
Unamortized debt issuance costs				(51)	(39)
Fair value adjustment				164	175
Long-term Debt, Current Maturities				(850)	(1,150)
Long-term Debt, Excluding Current Maturities				8,742	6,265
First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 22,651	20,751
First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				1.05%
Long-term Debt, Maturity Date				Dec. 31, 2023
First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.90%
Long-term Debt, Maturity Date				Dec. 31, 2052
Senior unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 8,324	6,324
Senior unsecured notes [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 8,139	6,139
Senior unsecured notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.75%
Long-term Debt, Maturity Date				Dec. 31, 2025
Senior unsecured notes [Member] | Minimum [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.75%
Long-term Debt, Maturity Date				Dec. 31, 2025
Senior unsecured notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.60%
Long-term Debt, Maturity Date				Dec. 31, 2052
Senior unsecured notes [Member] | Maximum [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.60%
Long-term Debt, Maturity Date				Dec. 31, 2052
Unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 4,250	4,000
Unsecured notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.25%
Long-term Debt, Maturity Date				Dec. 31, 2023
Unsecured notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.35%
Long-term Debt, Maturity Date				Dec. 31, 2052
Notes payable and other [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 86	86
Notes payable and other [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				1.64%
Long-term Debt, Maturity Date				Dec. 31, 2025
Notes payable and other [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.49%
Long-term Debt, Maturity Date				Dec. 31, 2053
Junior subordinated notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0	1,150
Junior subordinated notes [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0	1,150
Junior subordinated notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				3.50%
Long-term Debt, Maturity Date				Dec. 31, 2022
Junior subordinated notes [Member] | Maximum [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				3.50%
Long-term Debt, Maturity Date				Dec. 31, 2022
Long-term software licensing agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 25	9
Long-term software licensing agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.30%
Long-term Debt, Maturity Date				Dec. 31, 2024
Long-term software licensing agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				3.95%
Long-term Debt, Maturity Date				Dec. 31, 2025
Unsecured tax-exempt bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 33	143
Unsecured tax-exempt bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.00%
Long-term Debt, Maturity Date
Unsecured tax-exempt bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.05%
Long-term Debt, Maturity Date				Dec. 31, 2024
Medium-term notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 10	10
Medium-term notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.72%
Long-term Debt, Maturity Date				Dec. 31, 2027
Transition bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date
Loan agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 1,400	50
Loan agreement [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 300		$ 1,350	0
Loan agreement [Member] | Corporate, Non-Segment [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate		0.65%
Loan agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.00%
Long-term Debt, Maturity Date				Dec. 31, 2023
Loan agreement [Member] | Minimum [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.95%
Long-term Debt, Maturity Date				Dec. 31, 2023
Loan agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.15%
Long-term Debt, Maturity Date				Dec. 31, 2024
Loan agreement [Member] | Maximum [Member] | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.15%
Long-term Debt, Maturity Date				Dec. 31, 2024
Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 390	390
Loans Payable Two | Corporate, Non-Segment [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate		0.65%
Loans Payable Three | Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 250
Loans Payable Three | Corporate, Non-Segment [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate	0.65%
ComEd Financing III Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				206	206
ComEd Financing III Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 206	206
ComEd Financing III Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.35%
Long-term Debt, Maturity Date				Dec. 31, 2033
PECO Trust III Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 81	81
PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 81	81
PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.38%
PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				9.50%
Long-term Debt, Maturity Date				Dec. 31, 2028
PECO Trust IV Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 103	103
PECO Trust IV Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 103	103
PECO Trust IV Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.75%
Long-term Debt, Maturity Date				Dec. 31, 2033
Commonwealth Edison Co [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 10,637	9,887
Unamortized debt discount and premium, net				(27)	(27)
Unamortized debt issuance costs				(92)	(87)
Long-term Debt, Excluding Current Maturities				10,518	9,773
Long-term debt to financing trusts				205	205
Commonwealth Edison Co [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 10,629	9,879
Commonwealth Edison Co [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.20%
Long-term Debt, Maturity Date				Dec. 31, 2024
Commonwealth Edison Co [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.45%
Long-term Debt, Maturity Date				Dec. 31, 2052
Commonwealth Edison Co [Member] | Notes payable and other [Member]
Debt Instrument [Line Items]
Finance lease, liability				$ 8	8
Commonwealth Edison Co [Member] | Notes payable and other [Member] | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2053
Lessee, finance lease, discount rate				7.49%
Commonwealth Edison Co [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 206	206
Commonwealth Edison Co [Member] | First Mortgage Bonds | Subsequent Event [Member] | FMB490Feb2033
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.90%
Commonwealth Edison Co [Member] | First Mortgage Bonds | Subsequent Event [Member] | FMB530Feb2053
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			5.30%
Commonwealth Edison Co [Member] | First Mortgage | Subsequent Event [Member] | FMB490Feb2033
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 400
Commonwealth Edison Co [Member] | First Mortgage | Subsequent Event [Member] | FMB530Feb2053
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 575
Commonwealth Edison Co [Member] | ComEd Financing III Affiliate [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs				(1)	(1)
Long-term debt to financing trusts				205	205
Commonwealth Edison Co [Member] | ComEd Financing III Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 206	206
Commonwealth Edison Co [Member] | ComEd Financing III Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.35%
Commonwealth Edison Co [Member] | PECO Trust III Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 0	0
Commonwealth Edison Co [Member] | PECO Trust IV Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				0	0
PECO Energy Co [Member]
Debt Instrument [Line Items]
Long-term debt, gross				4,675	4,250
Unamortized debt discount and premium, net				(24)	(20)
Unamortized debt issuance costs				(39)	(33)
Long-term Debt, Current Maturities				(50)	(350)
Long-term Debt, Excluding Current Maturities				4,562	3,847
Long-term debt to financing trusts				184	184
PECO Energy Co [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 4,625	4,200
PECO Energy Co [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.80%
Long-term Debt, Maturity Date				Dec. 31, 2025
PECO Energy Co [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.95%
Long-term Debt, Maturity Date				Dec. 31, 2052
PECO Energy Co [Member] | Loan agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 50	50
PECO Energy Co [Member] | Loan agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.00%
Long-term Debt, Maturity Date				Dec. 31, 2023
PECO Energy Co [Member] | ComEd Financing III Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 0	0
PECO Energy Co [Member] | PECO Trust III Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				81	81
PECO Energy Co [Member] | PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 81	81
PECO Energy Co [Member] | PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.38%
PECO Energy Co [Member] | PECO Trust III Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				9.50%
Long-term Debt, Maturity Date				Dec. 31, 2028
PECO Energy Co [Member] | PECO Trust IV Affiliate [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 103	103
PECO Energy Co [Member] | PECO Trust IV Affiliate [Member] | Long-term debt to financing trusts [Member]
Debt Instrument [Line Items]
Long-term debt to financing trusts				$ 103	103
PECO Energy Co [Member] | PECO Trust IV Affiliate [Member] | Long-term debt to financing trusts [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.75%
Long-term Debt, Maturity Date				Dec. 31, 2033
Baltimore Gas and Electric Company [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 4,250	4,000
Unamortized debt discount and premium, net				(13)	(12)
Unamortized debt issuance costs				(30)	(27)
Long-term Debt, Current Maturities				(300)	(250)
Long-term Debt, Excluding Current Maturities				3,907	3,711
Baltimore Gas and Electric Company [Member] | Unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 4,250	4,000
Baltimore Gas and Electric Company [Member] | Unsecured notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.25%
Long-term Debt, Maturity Date				Dec. 31, 2023
Baltimore Gas and Electric Company [Member] | Unsecured notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.35%
Long-term Debt, Maturity Date				Dec. 31, 2052
Pepco Holdings LLC [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 7,701	7,084
Finance lease, liability				76	74
Unamortized debt discount and premium, net				4	4
Unamortized debt issuance costs				(47)	(36)
Fair value adjustment				462	495
Long-term debt due within one year				(591)	(399)
Long-term Debt, Excluding Current Maturities				7,529	7,148
Pepco Holdings LLC [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 7,397	6,672
Pepco Holdings LLC [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				1.05%
Long-term Debt, Maturity Date				Dec. 31, 2023
Pepco Holdings LLC [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.90%
Long-term Debt, Maturity Date				Dec. 31, 2052
Pepco Holdings LLC [Member] | Senior unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 185	185
Pepco Holdings LLC [Member] | Senior unsecured notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.45%
Long-term Debt, Maturity Date				Dec. 31, 2032
Pepco Holdings LLC [Member] | Finance Leases
Debt Instrument [Line Items]
Finance lease, liability				$ 76	74
Pepco Holdings LLC [Member] | Finance Leases | Minimum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2025
Pepco Holdings LLC [Member] | Finance Leases | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2030
Lessee, finance lease, discount rate				5.59%
Pepco Holdings LLC [Member] | Notes payable and other [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0	0
Pepco Holdings LLC [Member] | Notes payable and other [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.28%
Pepco Holdings LLC [Member] | Notes payable and other [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.49%
Long-term Debt, Maturity Date				Dec. 31, 2022
Pepco Holdings LLC [Member] | Unsecured tax-exempt bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 33	143
Pepco Holdings LLC [Member] | Unsecured tax-exempt bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.00%
Long-term Debt, Maturity Date
Pepco Holdings LLC [Member] | Unsecured tax-exempt bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.05%
Long-term Debt, Maturity Date				Dec. 31, 2024
Pepco Holdings LLC [Member] | Medium-term notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 10	10
Pepco Holdings LLC [Member] | Medium-term notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.72%
Long-term Debt, Maturity Date				Dec. 31, 2027
Pepco Holdings LLC [Member] | Transition bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date
Potomac Electric Power Company [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 3,800	3,486
Finance lease, liability				25	26
Unamortized debt discount and premium, net				2	2
Unamortized debt issuance costs				(51)	(43)
Long-term debt due within one year				(4)	(313)
Long-term Debt, Excluding Current Maturities				3,747	3,132
Potomac Electric Power Company [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 3,775	3,350
Potomac Electric Power Company [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.32%
Long-term Debt, Maturity Date				Dec. 31, 2024
Potomac Electric Power Company [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.90%
Long-term Debt, Maturity Date				Dec. 31, 2052
Potomac Electric Power Company [Member] | Finance Leases
Debt Instrument [Line Items]
Finance lease, liability				$ 25	26
Potomac Electric Power Company [Member] | Finance Leases | Minimum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2025
Potomac Electric Power Company [Member] | Finance Leases | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2029
Lessee, finance lease, discount rate				5.59%
Potomac Electric Power Company [Member] | Notes payable and other [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0	0
Potomac Electric Power Company [Member] | Notes payable and other [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.28%
Potomac Electric Power Company [Member] | Notes payable and other [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.49%
Long-term Debt, Maturity Date				Dec. 31, 2022
Potomac Electric Power Company [Member] | Unsecured tax-exempt bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0	110
Potomac Electric Power Company [Member] | Unsecured tax-exempt bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				1.70%
Long-term Debt, Maturity Date				Dec. 31, 2022
Delmarva Power & Light Company [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 1,949	1,821
Finance lease, liability				32	29
Unamortized debt discount and premium, net				0	0
Unamortized debt issuance costs				(11)	(11)
Long-term Debt, Current Maturities				(79)	(79)
Long-term debt due within one year				(584)	(83)
Long-term Debt, Excluding Current Maturities				1,354	1,727
Delmarva Power & Light Company [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 1,874	1,749
Delmarva Power & Light Company [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				1.05%
Long-term Debt, Maturity Date				Dec. 31, 2023
Delmarva Power & Light Company [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.27%
Long-term Debt, Maturity Date				Dec. 31, 2052
Delmarva Power & Light Company [Member] | Finance Leases
Debt Instrument [Line Items]
Finance lease, liability				$ 32	29
Delmarva Power & Light Company [Member] | Finance Leases | Minimum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2025
Delmarva Power & Light Company [Member] | Finance Leases | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2030
Lessee, finance lease, discount rate				5.39%
Delmarva Power & Light Company [Member] | Unsecured tax-exempt bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 33	33
Delmarva Power & Light Company [Member] | Unsecured tax-exempt bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.00%
Delmarva Power & Light Company [Member] | Unsecured tax-exempt bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.05%
Long-term Debt, Maturity Date				Dec. 31, 2024
Delmarva Power & Light Company [Member] | Medium-term notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 10	10
Delmarva Power & Light Company [Member] | Medium-term notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.72%
Long-term Debt, Maturity Date				Dec. 31, 2027
Atlantic City Electric Company [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 1,767	1,592
Finance lease, liability				19	19
Unamortized debt discount and premium, net				(1)	(1)
Unamortized debt issuance costs				(9)	(9)
Long-term debt due within one year				(3)	(3)
Long-term Debt, Excluding Current Maturities				1,754	1,579
Atlantic City Electric Company [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 1,748	1,573
Atlantic City Electric Company [Member] | First Mortgage Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				2.25%
Long-term Debt, Maturity Date				Dec. 31, 2024
Atlantic City Electric Company [Member] | First Mortgage Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.80%
Long-term Debt, Maturity Date				Dec. 31, 2052
Atlantic City Electric Company [Member] | Finance Leases
Debt Instrument [Line Items]
Finance lease, liability				$ 19	$ 19
Atlantic City Electric Company [Member] | Finance Leases | Minimum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2025
Atlantic City Electric Company [Member] | Finance Leases | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2030
Lessee, finance lease, discount rate				5.59%
Atlantic City Electric Company [Member] | Transition bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturity Date				Dec. 31, 2021
Delmarva Power & Light Co | Notes payable and other [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 0