Commitments and Contingencies, Fuel Contracts (Details) $ in Millions	Dec. 31, 2019 USD ($)
Coal
Fuel Contracts [Abstract]
2020	$ 171.3
2021	85.2
2022	51.9
2023	35.1
2024	0.9
Thereafter	2.6
Total	347.0
Nuclear Fuel
Fuel Contracts [Abstract]
2020	53.8
2021	102.5
2022	85.3
2023	103.0
2024	74.5
Thereafter	275.1
Total	694.2
Natural Gas Supply
Fuel Contracts [Abstract]
2020	36.8
2021	1.4
2022	0.8
2023	0.0
2024	0.0
Thereafter	0.0
Total	39.0
Natural Gas Storage and Transportation
Fuel Contracts [Abstract]
2020	133.0
2021	129.8
2022	124.3
2023	107.8
2024	101.1
Thereafter	273.6
Total	$ 869.6

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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