Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Jun. 30, 2022 USD ($)
Other Commitments [Line Items]
2022	$ 708
2023	466
2024	326
2025	242
2026	236
Thereafter	1,976
Total future minimum payments	3,954
Purchased Power [Member]
Other Commitments [Line Items]
2022	33
2023	0
2024	0
2025	0
2026	0
Thereafter	0
Total future minimum payments	33
Transportation [Member]
Other Commitments [Line Items]
2022	119
2023	235
2024	231
2025	218
2026	214
Thereafter	1,876
Total future minimum payments	2,893
Capital Projects [Member]
Other Commitments [Line Items]
2022	241
2023	153
2024	63
2025	1
2026	0
Thereafter	0
Total future minimum payments	458
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2022	287
2023	44
2024	0
2025	0
2026	0
Thereafter	0
Total future minimum payments	331
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2022	24
2023	30
2024	28
2025	20
2026	21
Thereafter	52
Total future minimum payments	175
Operating Leases [Member]
Other Commitments [Line Items]
2022	1
2023	3
2024	3
2025	2
2026	1
Thereafter	48
Total future minimum payments	58
Demand Side Management [Member]
Other Commitments [Line Items]
2022	3
2023	1
2024	1
2025	1
2026	0
Thereafter	0
Total future minimum payments	$ 6

Contractual obligation due after fourth year.

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

+ References

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Amount of contractual obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of contractual obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of contractual obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of contractual obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

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

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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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