Leases - Lessor - Operating Lease, Payments, Fiscal Year Maturity (Details) $ in Millions	Dec. 31, 2023 USD ($)
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	$ 6
2025	6
2026	6
2027	6
2028	5
Remaining years	22
Total	51
Commonwealth Edison Co
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	1
2025	1
2026	0
2027	0
2028	0
Remaining years	0
Total	2
PECO Energy Co
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	1
2025	1
2026	1
2027	0
2028	0
Remaining years	3
Total	6
Baltimore Gas and Electric Company
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
Remaining years	1
Total	1
Pepco Holdings LLC
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	4
2025	4
2026	5
2027	5
2028	5
Remaining years	18
Total	41
Potomac Electric Power Company
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
Remaining years	0
Total	0
Delmarva Power & Light Company
Schedule of Lessor, Operating Lease, Payments to be Received, Maturity [Line Items]
2024	4
2025	4
2026	4
2027	4
2028	4
Remaining years	18
Total	$ 38

[Line Items] for Schedule of Lessor, Operating Lease, Payments to be Received, Maturity

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- Definition

Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-12

+ Details

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- Definition

Amount of lease payment to be received by lessor for operating lease in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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