Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Sep. 30, 2022 USD ($)
Other Commitments [Line Items]
2022	$ 599
2023	976
2024	453
2025	315
2026	289
Thereafter	2,049
Total future minimum payments	4,681
Purchased Power [Member]
Other Commitments [Line Items]
2022	13
2023	0
2024	0
2025	0
2026	0
Thereafter	0
Total future minimum payments	13
Transportation [Member]
Other Commitments [Line Items]
2022	70
2023	267
2024	262
2025	248
2026	239
Thereafter	1,949
Total future minimum payments	3,035
Capital Projects [Member]
Other Commitments [Line Items]
2022	255
2023	166
2024	64
2025	3
2026	1
Thereafter	0
Total future minimum payments	489
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2022	245
2023	509
2024	94
2025	42
2026	27
Thereafter	0
Total future minimum payments	917
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2022	14
2023	30
2024	29
2025	20
2026	21
Thereafter	52
Total future minimum payments	166
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	1
2023	1
2024	1
2025	0
2026	0
Thereafter	0
Total future minimum payments	$ 3

Contractual obligation due after fourth year.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

No definition available.

+ Details

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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

No definition available.

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- Definition

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).

+ References

No definition available.

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- Definition

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).

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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