Supplemental Financial Information - Taxes Other Than Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Supplemental Statement of Operations Information [Line Items]
Utility taxes	$ 247	$ 226	$ 496	$ 447
Property	111	107	222	212
Payroll	34	33	67	67
Commonwealth Edison Co
Supplemental Statement of Operations Information [Line Items]
Utility taxes	79	73	159	148
Property	8	10	18	18
Payroll	9	9	16	18
PECO Energy Co
Supplemental Statement of Operations Information [Line Items]
Utility taxes	47	42	98	83
Property	4	5	9	9
Payroll	5	4	9	9
Baltimore Gas and Electric Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	33	31	58	54
Property	57	53	114	107
Payroll	5	5	10	9
Pepco Holdings LLC
Supplemental Statement of Operations Information [Line Items]
Utility taxes	88	80	181	162
Property	40	39	80	78
Payroll	8	7	15	14
Potomac Electric Power Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	80	72	164	146
Property	27	26	55	53
Payroll	2	2	3	4
Delmarva Power and Light Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	7	6	15	14
Property	12	12	24	23
Payroll	1	1	2	2
Atlantic City Electric Company
Supplemental Statement of Operations Information [Line Items]
Utility taxes	1	0	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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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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