Commitments and Contingencies - Schedule of Commercial Commitments (Details) $ in Millions	Dec. 31, 2023 USD ($)
Guarantor Obligations [Line Items]
Other Commitment	$ 638
Other Commitments, Due in Next Twelve Months	231
Other Commitment, to be Paid, Year Two	7
Other Commitment, to be Paid, Year Three	6
Other Commitment, to be Paid, Year Four	4
Other Commitment, to be Paid, Year Five	84
Other Commitment, to be Paid, after Year Five	306
Guarantee obligations maximum exposure	61
Commonwealth Edison Co
Guarantor Obligations [Line Items]
Other Commitment	263
Other Commitments, Due in Next Twelve Months	61
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	200
PECO Energy Co
Guarantor Obligations [Line Items]
Other Commitment	181
Other Commitments, Due in Next Twelve Months	3
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	78
Other Commitment, to be Paid, after Year Five	100
Baltimore Gas and Electric Company
Guarantor Obligations [Line Items]
Other Commitment	11
Other Commitments, Due in Next Twelve Months	11
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Pepco Holdings LLC
Guarantor Obligations [Line Items]
Other Commitment	123
Other Commitments, Due in Next Twelve Months	96
Other Commitment, to be Paid, Year Two	5
Other Commitment, to be Paid, Year Three	6
Other Commitment, to be Paid, Year Four	4
Other Commitment, to be Paid, Year Five	6
Other Commitment, to be Paid, after Year Five	6
Guarantee obligations maximum exposure	61
Potomac Electric Power Company
Guarantor Obligations [Line Items]
Other Commitment	93
Other Commitments, Due in Next Twelve Months	84
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	2
Other Commitment, to be Paid, Year Four	1
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	2
Guarantee obligations maximum exposure	20
Delmarva Power & Light Company
Guarantor Obligations [Line Items]
Other Commitment	18
Other Commitments, Due in Next Twelve Months	7
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	3
Other Commitment, to be Paid, Year Four	2
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	2
Guarantee obligations maximum exposure	24
Atlantic City Electric Company
Guarantor Obligations [Line Items]
Other Commitment	12
Other Commitments, Due in Next Twelve Months	5
Other Commitment, to be Paid, Year Two	1
Other Commitment, to be Paid, Year Three	1
Other Commitment, to be Paid, Year Four	1
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	2
Guarantee obligations maximum exposure	17
Financial Standby Letter of Credit [Member]
Guarantor Obligations [Line Items]
Other Commitment	29
Other Commitments, Due in Next Twelve Months	27
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Financial Standby Letter of Credit [Member] | Commonwealth Edison Co
Guarantor Obligations [Line Items]
Other Commitment	17
Other Commitments, Due in Next Twelve Months	15
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Financial Standby Letter of Credit [Member] | PECO Energy Co
Guarantor Obligations [Line Items]
Other Commitment	1
Other Commitments, Due in Next Twelve Months	1
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Financial Standby Letter of Credit [Member] | Baltimore Gas and Electric Company
Guarantor Obligations [Line Items]
Other Commitment	8
Other Commitments, Due in Next Twelve Months	8
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member]
Guarantor Obligations [Line Items]
Other Commitment	204
Other Commitments, Due in Next Twelve Months	204
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Commonwealth Edison Co
Guarantor Obligations [Line Items]
Other Commitment	46
Other Commitments, Due in Next Twelve Months	46
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | PECO Energy Co
Guarantor Obligations [Line Items]
Other Commitment	2
Other Commitments, Due in Next Twelve Months	2
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Baltimore Gas and Electric Company
Guarantor Obligations [Line Items]
Other Commitment	3
Other Commitments, Due in Next Twelve Months	3
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Pepco Holdings LLC
Guarantor Obligations [Line Items]
Other Commitment	96
Other Commitments, Due in Next Twelve Months	96
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Potomac Electric Power Company
Guarantor Obligations [Line Items]
Other Commitment	84
Other Commitments, Due in Next Twelve Months	84
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Delmarva Power & Light Company
Guarantor Obligations [Line Items]
Other Commitment	7
Other Commitments, Due in Next Twelve Months	7
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Surety Bond [Member] | Atlantic City Electric Company
Guarantor Obligations [Line Items]
Other Commitment	5
Other Commitments, Due in Next Twelve Months	5
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	0
Guarantee of Indebtedness of Others [Member]
Guarantor Obligations [Line Items]
Other Commitment	378
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	78
Other Commitment, to be Paid, after Year Five	300
Guarantee of Indebtedness of Others [Member] | Commonwealth Edison Co
Guarantor Obligations [Line Items]
Other Commitment	200
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	0
Other Commitment, to be Paid, after Year Five	200
Guarantee of Indebtedness of Others [Member] | PECO Energy Co
Guarantor Obligations [Line Items]
Other Commitment	178
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	0
Other Commitment, to be Paid, Year Three	0
Other Commitment, to be Paid, Year Four	0
Other Commitment, to be Paid, Year Five	78
Other Commitment, to be Paid, after Year Five	100
Guarantee Obligations [Member]
Guarantor Obligations [Line Items]
Other Commitment	27
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	5
Other Commitment, to be Paid, Year Three	6
Other Commitment, to be Paid, Year Four	4
Other Commitment, to be Paid, Year Five	6
Other Commitment, to be Paid, after Year Five	6
Guarantee Obligations [Member] | Pepco Holdings LLC
Guarantor Obligations [Line Items]
Other Commitment	27
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	5
Other Commitment, to be Paid, Year Three	6
Other Commitment, to be Paid, Year Four	4
Other Commitment, to be Paid, Year Five	6
Other Commitment, to be Paid, after Year Five	6
Guarantee Obligations [Member] | Potomac Electric Power Company
Guarantor Obligations [Line Items]
Other Commitment	9
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	2
Other Commitment, to be Paid, Year Four	1
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	2
Guarantee Obligations [Member] | Delmarva Power & Light Company
Guarantor Obligations [Line Items]
Other Commitment	11
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	2
Other Commitment, to be Paid, Year Three	3
Other Commitment, to be Paid, Year Four	2
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	2
Guarantee Obligations [Member] | Atlantic City Electric Company
Guarantor Obligations [Line Items]
Other Commitment	7
Other Commitments, Due in Next Twelve Months	0
Other Commitment, to be Paid, Year Two	1
Other Commitment, to be Paid, Year Three	1
Other Commitment, to be Paid, Year Four	1
Other Commitment, to be Paid, Year Five	2
Other Commitment, to be Paid, after Year Five	$ 2
Minimum
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Minimum | Commonwealth Edison Co
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Minimum | PECO Energy Co
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Minimum | Baltimore Gas and Electric Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	19 years
Minimum | Pepco Holdings LLC
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Minimum | Potomac Electric Power Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Minimum | Delmarva Power & Light Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	8 years
Minimum | Guarantee Obligations [Member]
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	1 year
Maximum
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	79 years
Maximum | Commonwealth Edison Co
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	13 years
Maximum | PECO Energy Co
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	79 years
Maximum | Baltimore Gas and Electric Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	19 years
Maximum | Pepco Holdings LLC
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	9 years
Maximum | Potomac Electric Power Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	2 years
Maximum | Delmarva Power & Light Company
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	9 years
Maximum | Guarantee Obligations [Member]
Guarantor Obligations [Line Items]
Lessor, Operating Lease, Term of Contract	8 years