Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Sep. 30, 2024 USD ($)
Other Commitments [Line Items]
2024	$ 603
2025	374
2026	214
2027	210
2028	157
Thereafter	1,428
Total future minimum payments	2,986
Transportation [Member]
Other Commitments [Line Items]
2024	35
2025	146
2026	145
2027	177
2028	138
Thereafter	1,320
Total future minimum payments	1,961
Capital Projects [Member]
Other Commitments [Line Items]
2024	496
2025	54
2026	14
2027	5
2028	0
Thereafter	0
Total future minimum payments	569
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2024	60
2025	144
2026	30
2027	4
2028	1
Thereafter	0
Total future minimum payments	239
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2024	6
2025	22
2026	23
2027	22
2028	17
Thereafter	33
Total future minimum payments	123
Other [Member]
Other Commitments [Line Items]
2024	6
2025	8
2026	2
2027	2
2028	1
Thereafter	75
Total future minimum payments	$ 94

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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Amount of contractual obligation to be paid in remainder of current fiscal year.

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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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