Commitments (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Finance and Operating Leases
2021	$ 16,068
2022	15,878
2023	15,657
2024	15,183
2025	15,021
Thereafter	$ 41,595
Scherer Unit No. 2
Long-term Purchase Commitment [Line Items]
Ownership interest (as a percent)	60.00%
Coal
Long-term Purchase Commitment [Line Items]
2021	$ 5,168
2022	3,017
2023	0
2024	0
2025	0
Thereafter	0
Nuclear Fuel
Long-term Purchase Commitment [Line Items]
2021	73,500
2022	33,060
2023	17,340
2024	22,650
2025	11,250
Thereafter	15,930
Gas Transportation
Long-term Purchase Commitment [Line Items]
2021	63,385
2022	53,268
2023	48,707
2024	48,034
2025	46,350
Thereafter	746,160
Maintenance Agreements
Long-term Purchase Commitment [Line Items]
Cancellation obligation	54,007
2021	14,429
2022	14,896
2023	3,325
2024	30,316
2025	43,212
Thereafter	176,751
Asset Retirement Obligations
Long-term Purchase Commitment [Line Items]
2021	17,821
2022	31,780
2023	34,372
2024	41,840
2025	74,077
Thereafter	$ 3,400,140

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

No definition available.

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ Details

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- Definition

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.

+ Details

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- Definition

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.

+ Details

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- Definition

n/a

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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 http://asc.fasb.org/extlink&oid=115995737&loc=d3e659983-123033

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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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- Definition

Minimum amount of purchase arrangement maturing after the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

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- Definition

Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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