Leases - Lessee Future Minimum Operating Lease Maturity Payments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	$ 49
2025	47
2026	43
2027	41
2028	41
Remaining years	130
Total	351
Interest	65
Total operating lease liabilities	286
Commonwealth Edison Co
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
Remaining years	0
Total	0
Interest	0
Total operating lease liabilities	0
PECO Energy Co
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
Remaining years	0
Total	0
Interest	0
Total operating lease liabilities	0
Baltimore Gas and Electric Company
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	4
2025	4
2026	4
2027	2
2028	2
Remaining years	22
Total	38
Interest	17
Total operating lease liabilities	21
Pepco Holdings LLC
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	36
2025	34
2026	30
2027	30
2028	30
Remaining years	40
Total	200
Interest	29
Total operating lease liabilities	171
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2024	16
2025	16
2026	16
2027	14
2028	10
Remaining years	8
Total	80
Interest	6
Total finance lease liabilities	74	$ 76
Potomac Electric Power Company
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	7
2025	5
2026	5
2027	4
2028	4
Remaining years	16
Total	41
Interest	6
Total operating lease liabilities	35
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2024	6
2025	6
2026	6
2027	5
2028	3
Remaining years	2
Total	28
Interest	2
Total finance lease liabilities	26	25
Delmarva Power & Light Company
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	9
2025	8
2026	5
2027	6
2028	6
Remaining years	21
Total	55
Interest	12
Total operating lease liabilities	43
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2024	6
2025	6
2026	6
2027	6
2028	4
Remaining years	3
Total	31
Interest	2
Total finance lease liabilities	29	32
Atlantic City Electric Company
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2024	3
2025	3
2026	1
2027	1
2028	1
Remaining years	1
Total	10
Interest	1
Total operating lease liabilities	9
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2024	4
2025	4
2026	4
2027	3
2028	3
Remaining years	3
Total	21
Interest	2
Total finance lease liabilities	$ 19	$ 19

Schedule of Lessee, Finance Lease, Liability, Maturity

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Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

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