Commitments and Contingencies - Schedule of Commercial Commitments (Details) $ in Millions |
Dec. 31, 2021
USD ($)
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
$ 3,814
|
Other Commitments, Due in Next Twelve Months |
3,285
|
Other Commitment, to be Paid, Year Two |
123
|
Other Commitment, to be Paid, Year Three |
8
|
Other Commitment, to be Paid, Year Four |
6
|
Other Commitment, to be Paid, Year Five |
5
|
Other Commitment, to be Paid, after Year Five |
387
|
Guarantee obligations maximum exposure |
75
|
Commonwealth Edison Co [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
224
|
Other Commitments, Due in Next Twelve Months |
22
|
Other Commitment, to be Paid, Year Two |
0
|
Other Commitment, to be Paid, Year Three |
2
|
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 [Member] |
|
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 |
0
|
Other Commitment, to be Paid, after Year Five |
178
|
Baltimore Gas and Electric Company [Member] |
|
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
|
Pepco Holdings LLC [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
54
|
Other Commitments, Due in Next Twelve Months |
23
|
Other Commitment, to be Paid, Year Two |
5
|
Other Commitment, to be Paid, Year Three |
6
|
Other Commitment, to be Paid, Year Four |
6
|
Other Commitment, to be Paid, Year Five |
5
|
Other Commitment, to be Paid, after Year Five |
9
|
Guarantee obligations maximum exposure |
75
|
Potomac Electric Power Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
24
|
Other Commitments, Due in Next Twelve Months |
14
|
Other Commitment, to be Paid, Year Two |
1
|
Other Commitment, to be Paid, Year Three |
2
|
Other Commitment, to be Paid, Year Four |
2
|
Other Commitment, to be Paid, Year Five |
2
|
Other Commitment, to be Paid, after Year Five |
3
|
Guarantee obligations maximum exposure |
25
|
Delmarva Power & Light Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
18
|
Other Commitments, Due in Next Twelve Months |
5
|
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 |
4
|
Guarantee obligations maximum exposure |
31
|
Atlantic City Electric Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
12
|
Other Commitments, Due in Next Twelve Months |
4
|
Other Commitment, to be Paid, Year Two |
2
|
Other Commitment, to be Paid, Year Three |
1
|
Other Commitment, to be Paid, Year Four |
2
|
Other Commitment, to be Paid, Year Five |
1
|
Other Commitment, to be Paid, after Year Five |
2
|
Guarantee obligations maximum exposure |
19
|
Financial Standby Letter of Credit [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
2,397
|
Other Commitments, Due in Next Twelve Months |
2,296
|
Other Commitment, to be Paid, Year Two |
101
|
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 [Member] |
|
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
|
Financial Standby Letter of Credit [Member] | PECO Energy Co [Member] |
|
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 [Member] |
|
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] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
1,008
|
Other Commitments, Due in Next Twelve Months |
989
|
Other Commitment, to be Paid, Year Two |
17
|
Other Commitment, to be Paid, Year Three |
2
|
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 [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
17
|
Other Commitments, Due in Next Twelve Months |
15
|
Other Commitment, to be Paid, Year Two |
0
|
Other Commitment, to be Paid, Year Three |
2
|
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 [Member] |
|
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 [Member] |
|
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 [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
23
|
Other Commitments, Due in Next Twelve Months |
23
|
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 [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
14
|
Other Commitments, Due in Next Twelve Months |
14
|
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 [Member] |
|
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
|
Surety Bond [Member] | Atlantic City Electric Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
4
|
Other Commitments, Due in Next Twelve Months |
4
|
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 |
0
|
Other Commitment, to be Paid, after Year Five |
378
|
Guarantee of Indebtedness of Others [Member] | Commonwealth Edison Co [Member] |
|
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 [Member] |
|
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 |
0
|
Other Commitment, to be Paid, after Year Five |
178
|
Guarantee Obligations [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
31
|
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 |
6
|
Other Commitment, to be Paid, Year Five |
5
|
Other Commitment, to be Paid, after Year Five |
9
|
Guarantee Obligations [Member] | Pepco Holdings LLC [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
31
|
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 |
6
|
Other Commitment, to be Paid, Year Five |
5
|
Other Commitment, to be Paid, after Year Five |
9
|
Guarantee Obligations [Member] | Potomac Electric Power Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
10
|
Other Commitments, Due in Next Twelve Months |
0
|
Other Commitment, to be Paid, Year Two |
1
|
Other Commitment, to be Paid, Year Three |
2
|
Other Commitment, to be Paid, Year Four |
2
|
Other Commitment, to be Paid, Year Five |
2
|
Other Commitment, to be Paid, after Year Five |
3
|
Guarantee Obligations [Member] | Delmarva Power & Light Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
13
|
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 |
4
|
Guarantee Obligations [Member] | Atlantic City Electric Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Other Commitment |
8
|
Other Commitments, Due in Next Twelve Months |
0
|
Other Commitment, to be Paid, Year Two |
2
|
Other Commitment, to be Paid, Year Three |
1
|
Other Commitment, to be Paid, Year Four |
2
|
Other Commitment, to be Paid, Year Five |
1
|
Other Commitment, to be Paid, after Year Five |
$ 2
|
Minimum [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Minimum [Member] | Commonwealth Edison Co [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Minimum [Member] | PECO Energy Co [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Minimum [Member] | Baltimore Gas and Electric Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
21 years
|
Minimum [Member] | Pepco Holdings LLC [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Minimum [Member] | Potomac Electric Power Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Minimum [Member] | Delmarva Power & Light Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
10 years
|
Minimum [Member] | Guarantee Obligations [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
1 year
|
Maximum [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
81 years
|
Maximum [Member] | Commonwealth Edison Co [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
15 years
|
Maximum [Member] | PECO Energy Co [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
81 years
|
Maximum [Member] | Baltimore Gas and Electric Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
21 years
|
Maximum [Member] | Pepco Holdings LLC [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
11 years
|
Maximum [Member] | Potomac Electric Power Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
4 years
|
Maximum [Member] | Delmarva Power & Light Company [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
11 years
|
Maximum [Member] | Guarantee Obligations [Member] |
|
Guarantor Obligations [Line Items] |
|
Lessor, Operating Lease, Term of Contract |
8 years
|