Lessee - Lessee Future Minimum Operating Lease Maturity Payments (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	$ 52
2024	45
2025	43
2026	39
2027	39
Remaining years	161
Lessee, Operating Lease, Liability, to be Paid	379
Interest	73
Operating Lease, Liability	306	$ 315
Total property, plant and equipment	85,006	78,988
Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	4,534	3,698
Commonwealth Edison Co [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	2
2024	0
2025	0
2026	0
2027	0
Remaining years	0
Lessee, Operating Lease, Liability, to be Paid	2
Interest	0
Operating Lease, Liability	2	5
Total property, plant and equipment	34,186	32,094
Commonwealth Edison Co [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	1,174	918
PECO Energy Co [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	0
2024	0
2025	0
2026	0
2027	0
Remaining years	1
Lessee, Operating Lease, Liability, to be Paid	1
Interest	0
Operating Lease, Liability	1	1
Total property, plant and equipment	16,203	15,081
PECO Energy Co [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	744	620
Baltimore Gas and Electric Company [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	1
2024	0
2025	0
2026	0
2027	0
Remaining years	18
Lessee, Operating Lease, Liability, to be Paid	19
Interest	15
Operating Lease, Liability	4	19
Total property, plant and equipment	15,921	14,876
Baltimore Gas and Electric Company [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	487	554
Pepco Holdings LLC [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	37
2024	35
2025	34
2026	30
2027	29
Remaining years	67
Lessee, Operating Lease, Liability, to be Paid	232
Interest	34
Operating Lease, Liability	198	226
Total property, plant and equipment	20,304	18,606
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2023	14
2024	14
2025	15
2026	15
2027	12
Remaining years	12
Finance Lease, Liability, to be Paid	82
Interest	6
Finance lease, liability	76	74
Pepco Holdings LLC [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	2,101	1,590
Potomac Electric Power Company [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	7
2024	6
2025	6
2026	5
2027	4
Remaining years	20
Lessee, Operating Lease, Liability, to be Paid	48
Interest	8
Operating Lease, Liability	40	46
Total property, plant and equipment	12,861	11,979
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2023	5
2024	5
2025	5
2026	5
2027	4
Remaining years	4
Finance Lease, Liability, to be Paid	28
Interest	3
Finance lease, liability	25	26
Potomac Electric Power Company [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	1,526	1,118
Delmarva Power & Light Company [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	10
2024	9
2025	7
2026	5
2027	6
Remaining years	25
Lessee, Operating Lease, Liability, to be Paid	62
Interest	12
Operating Lease, Liability	50	57
Total property, plant and equipment	6,592	6,195
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2023	6
2024	6
2025	6
2026	6
2027	5
Remaining years	5
Finance Lease, Liability, to be Paid	34
Interest	2
Finance lease, liability	32	29
Delmarva Power & Light Company [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	271	229
Atlantic City Electric Company [Member]
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
2023	4
2024	3
2025	2
2026	1
2027	1
Remaining years	0
Lessee, Operating Lease, Liability, to be Paid	11
Interest	1
Operating Lease, Liability	10	12
Total property, plant and equipment	5,541	5,149
Schedule of Lessee, Finance Lease, Liability, Maturity [Line Items]
2023	3
2024	3
2025	4
2026	4
2027	3
Remaining years	3
Finance Lease, Liability, to be Paid	20
Interest	1
Finance lease, liability	19	19
Atlantic City Electric Company [Member] \| Construction work in progress
Schedule of Lessee, Operating Lease, Liability, Maturity [Line Items]
Total property, plant and equipment	$ 296	$ 242

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid 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).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid 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).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid 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).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid 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).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid 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).

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Amount of lessee's undiscounted obligation for lease payment for operating lease due 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).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid 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).

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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