Commitments (Details)	12 Months Ended
Dec. 31, 2022 USD ($)
Finance and Operating Leases
2023	$ 16,273,000
2024	15,799,000
2025	15,590,000
2026	15,299,000
2027	15,021,000
Thereafter	$ 11,551,000
Scherer Unit No. 2
Long-term Purchase Commitment [Line Items]
Ownership interest (as a percent)	60.00%
Coal
Long-term Purchase Commitment [Line Items]
2023	$ 26,891,000
2024	26,070,000
2025	10,426,000
Nuclear Fuel
Long-term Purchase Commitment [Line Items]
2023	78,780,000
2024	39,690,000
2025	32,280,000
2026	28,980,000
2027	26,580,000
Thereafter	67,170,000
Gas Transportation
Long-term Purchase Commitment [Line Items]
2023	63,850,000
2024	62,818,000
2025	62,775,000
2026	68,872,000
2027	67,188,000
Thereafter	824,627,000
Maintenance Agreements
Long-term Purchase Commitment [Line Items]
Cancellation obligation	96,796,000
2023	29,720,000
2024	57,749,000
2025	43,025,000
2026	15,736,000
2027	3,237,000
Thereafter	316,160,000
Asset Retirement Obligations
Long-term Purchase Commitment [Line Items]
2023	16,709,000
2024	52,003,000
2025	46,128,000
2026	49,445,000
2027	67,384,000
Thereafter	$ 3,416,582,000

The amount of convenience penalties which are to be paid if theres is any cancellation of contractual obligation.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due after fifth fiscal year following latest fiscal year.

+ References

No definition available.

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Lessee, Finance Lease and Operating Lease, Liability, Payments, Due Next Twelve Months

+ References

No definition available.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in fifth fiscal year following latest fiscal year.

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No definition available.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in fourth fiscal year following latest fiscal year.

+ References

No definition available.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in third fiscal year following latest fiscal year.

+ References

No definition available.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in second fiscal year following latest fiscal year.

+ References

No definition available.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI https://asc.fasb.org/extlink&oid=122136288&loc=d3e659983-123033

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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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Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. 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 purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. 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 purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. 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 purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. 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 purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. 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 purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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