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Regulatory Matters - Schedule of Composition of Regulatory Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	$ 1,416	$ 1,416
Current regulatory liabilities	24	0
Total regulatory liabilities	1,440	1,416
Income taxes recovered through rates
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	959	1,016
Removal costs recovered through rates
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	248	245
PFAS Multi-district litigation settlements
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	91	0
Postretirement benefit liability
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	43	71
Other
Regulatory Liabilities [Line Items]
Total (non-current) regulatory liabilities	$ 75	$ 84

X

- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477571/980-405-25-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477571/980-405-25-1

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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