Commitments (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Finance and Operating Leases
2020	$ 16,348
2021	15,744
2022	15,554
2023	15,333
2024	15,021
Thereafter	$ 56,617
Scherer Unit No. 2
Long-term Purchase Commitment [Line Items]
Ownership interest (as a percent)	60.00%
Coal
Long-term Purchase Commitment [Line Items]
2020	$ 13,019
2021	5,231
2022	2,524
2023	0
2024	0
Thereafter	0
Nuclear Fuel
Long-term Purchase Commitment [Line Items]
2020	55,300
2021	36,200
2022	31,200
2023	18,400
2024	20,800
Thereafter	14,300
Gas Transportation
Long-term Purchase Commitment [Line Items]
2020	63,985
2021	63,444
2022	53,643
2023	49,044
2024	46,686
Thereafter	798,660
Maintenance Agreements
Long-term Purchase Commitment [Line Items]
Cancellation obligation	80,000
2020	53,911
2021	14,461
2022	14,929
2023	3,330
2024	29,750
Thereafter	218,456
Asset Retirement Obligations
Long-term Purchase Commitment [Line Items]
2020	6,623
2021	19,206
2022	33,742
2023	32,932
2024	42,504
Thereafter	$ 3,453,280

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.

+ Details

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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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