Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Jun. 30, 2024 USD ($)
Other Commitments [Line Items]
2024	$ 726
2025	277
2026	187
2027	164
2028	121
Thereafter	948
Total future minimum payments	2,423
Transportation [Member]
Other Commitments [Line Items]
2024	71
2025	131
2026	130
2027	130
2028	102
Thereafter	840
Total future minimum payments	1,404
Capital Projects [Member]
Other Commitments [Line Items]
2024	515
2025	47
2026	15
2027	6
2028	0
Thereafter	0
Total future minimum payments	583
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2024	124
2025	69
2026	17
2027	4
2028	1
Thereafter	0
Total future minimum payments	215
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2024	7
2025	22
2026	23
2027	22
2028	17
Thereafter	33
Total future minimum payments	124
Other [Member]
Other Commitments [Line Items]
2024	9
2025	8
2026	2
2027	2
2028	1
Thereafter	75
Total future minimum payments	$ 97

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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