Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Regulatory assets:
Regulatory assets	$ 909	$ 988
Less: Current portion	80	161
Long-term regulatory assets	829	827
Regulatory liabilities:
Regulatory liabilities	840	795
Less: Current portion	103	94
Long-term regulatory liabilities	737	701
Regulatory Tax Asset [Member]
Regulatory assets:
Regulatory assets	114	112
Cost-Recovery Clauses [Member]
Regulatory assets:
Regulatory assets	15	94
Capital Cost Recovery for Early Retired Assets [Member]
Regulatory assets:
Regulatory assets	515	507
Postretirement Benefits [Member]
Regulatory assets:
Regulatory assets	235	236
Storm Reserve [Member]
Regulatory assets:
Regulatory assets	0	7
Other [Member]
Regulatory assets:
Regulatory assets	30	32
Regulatory Tax Liability [Member] \| Non-Current Liabilities [Member]
Regulatory liabilities:
Regulatory liabilities	463	477
Cost-recovery Clauses - Deferred Balances [Member]
Regulatory liabilities:
Regulatory liabilities	22	20
Accumulated Reserve - Cost of Removal [Member]
Regulatory liabilities:
Regulatory liabilities	304	271
Storm Reserve [Member]
Regulatory liabilities:
Regulatory liabilities	5	0
Other [Member]
Regulatory liabilities:
Regulatory liabilities	$ 46	$ 27

Regulatory assets.

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Regulatory liabilities.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481878/980-340-50-1

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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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
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-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481854/980-405-25-1

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

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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
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-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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