Supplemental Financial Information - Taxes Other Than Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Supplemental Statement of Operations Information [Line Items]
Utility taxes	$ 253	$ 247	$ 528	$ 496
Property	124	111	250	222
Payroll	36	34	70	67
Commonwealth Edison Co
Supplemental Statement of Operations Information [Line Items]
Utility taxes	86	79	171	159
Property	10	8	20	18
Payroll	9	9	18	16
PECO Energy Co
Supplemental Statement of Operations Information [Line Items]
Utility taxes	51	47	109	98
Property	5	4	10	9
Payroll	5	5	10	9
Baltimore Gas and Electric Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	27	33	63	58
Property	63	57	126	114
Payroll	4	5	8	10
Pepco Holdings LLC
Supplemental Statement of Operations Information [Line Items]
Utility taxes	89	88	185	181
Property	46	40	93	80
Payroll	9	8	17	15
Potomac Electric Power Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	81	80	167	164
Property	30	27	60	55
Payroll	2	2	4	3
Delmarva Power and Light Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	7	7	16	15
Property	15	12	31	24
Payroll	1	1	2	2
Atlantic City Electric Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	1	1	2	2
Property	1	1	1	1
Payroll	$ 1	$ 1	$ 2	$ 2

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- Definition

Amount of labor-related expenses classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(4))
-Publisher FASB
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- Definition

A tax based on the assessed value of real estate by the local government. The tax is usually based on the value of property (including the land).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 720
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
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-Publisher FASB
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Amount of operating expense for taxes other than income taxes of regulated operation.

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-Topic 220
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-Section S99
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