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Commitments, Guarantees and Contingencies Minimum Payments for Certain Long-Term Commitments (Details)
$ in Millions

Dec. 31, 2018

USD ($)

Coal, Rail and Shipping Contracts [Member]

Minimum Annual Payments for Certain Long-Term Commitments [Line Items]

Minimum Payments in 2019

$ 20.8

Minimum Payments in 2020

9.0

Minimum Payments in 2021

7.5

Minimum Payments in 2022

0.0

Minimum Payments in 2023

0.0

Minimum Payments Thereafter

0.0

Leasing Agreements [Member]

Minimum Annual Payments for Certain Long-Term Commitments [Line Items]

Minimum Payments in 2019

9.9

Minimum Payments in 2020

7.9

Minimum Payments in 2021

6.1

Minimum Payments in 2022

4.9

Minimum Payments in 2023

3.1

Minimum Payments Thereafter

9.4

Easements [Member]

Minimum Annual Payments for Certain Long-Term Commitments [Line Items]

Minimum Payments in 2019

4.8

Minimum Payments in 2020

4.9

Minimum Payments in 2021

4.9

Minimum Payments in 2022

5.0

Minimum Payments in 2023

5.1

Minimum Payments Thereafter

136.3

Long-Term Service Agreements [Member]

Minimum Annual Payments for Certain Long-Term Commitments [Line Items]

Minimum Payments in 2019

31.6

^[1]

Minimum Payments in 2020

0.3

^[1]

Minimum Payments in 2021

0.3

^[1]

Minimum Payments in 2022

0.0

^[1]

Minimum Payments in 2023

0.0

^[1]

Minimum Payments Thereafter

0.1

^[1]

PPAs [Member]

Minimum Annual Payments for Certain Long-Term Commitments [Line Items]

Minimum Payments in 2019

107.3

^[2]

Minimum Payments in 2020

115.3

^[2]

Minimum Payments in 2021

145.4

^[2]

Minimum Payments in 2022

145.7

^[2]

Minimum Payments in 2023

145.8

^[2]

Minimum Payments Thereafter

$ 1,550.7

^[2]

[1]	Consists of long-term service agreements for wind energy facilities.
[2]	Does not include the agreement with Manitoba Hydro expiring in 2022, as this contract is for surplus energy only; Oliver Wind I and Oliver Wind II, as Minnesota Power only pays for energy as it is delivered; and the agreement with Nobles 2 commencing in 2020 as it is subject to construction of a wind energy facility. (See Power Purchase Agreements.)

X

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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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.

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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.

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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.

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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.

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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.

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+ References

No definition available.

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