Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Other Commitments [Line Items]
2024	$ 908
2025	299
2026	220
2027	154
2028	116
Thereafter	941
Total future minimum payments	2,638
Purchased Power [Member]
Other Commitments [Line Items]
2024	4
2025	0
2026	0
2027	0
2028	0
Thereafter	0
Total future minimum payments	4
Transportation [Member]
Other Commitments [Line Items]
2024	135
2025	128
2026	125
2027	125
2028	97
Thereafter	833
Total future minimum payments	1,443
Capital Projects [Member]
Other Commitments [Line Items]
2024	533
2025	81
2026	53
2027	1
2028	0
Thereafter	0
Total future minimum payments	668
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2024	194
2025	60
2026	17
2027	4
2028	1
Thereafter	0
Total future minimum payments	276
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2024	34
2025	22
2026	23
2027	22
2028	17
Thereafter	33
Total future minimum payments	151
Operating Leases [Member]
Other Commitments [Line Items]
2024	3
2025	3
2026	1
2027	1
2028	1
Thereafter	75
Total future minimum payments	84
Demand Side Management [Member]
Other Commitments [Line Items]
2024	5
2025	5
2026	1
2027	1
2028	0
Thereafter	0
Total future minimum payments	$ 12

Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

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+ References

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+ References

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+ References

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+ References

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+ References

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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.

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