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Commitments, Guarantees and Contingencies Minimum Payments for Certain Long-Term Commitments (Details) $ in Millions | Dec. 31, 2021 USD ($)
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Capital Purchase Obligations [Member] |  |
Minimum Annual Payments for Certain Long-Term Commitments [Line Items] |  |
Minimum Payments in 2022 | $ 50.7 |
Minimum Payments in 2023 | 0.1 |
Minimum Payments in 2024 | 0.0 |
Minimum Payments in 2025 | 0.0 |
Minimum Payments in 2026 | 0.0 |
Minimum Payments Thereafter | 0.0 |
Easements [Member] |  |
Minimum Annual Payments for Certain Long-Term Commitments [Line Items] |  |
Minimum Payments in 2022 | 8.2 | [1]
Minimum Payments in 2023 | 8.4 | [1]
Minimum Payments in 2024 | 8.4 | [1]
Minimum Payments in 2025 | 8.8 | [1]
Minimum Payments in 2026 | 9.2 | [1]
Minimum Payments Thereafter | 239.7 | [1]
PPAs [Member] |  |
Minimum Annual Payments for Certain Long-Term Commitments [Line Items] |  |
Minimum Payments in 2022 | 141.1 | [2]
Minimum Payments in 2023 | 140.7 | [2]
Minimum Payments in 2024 | 133.5 | [2]
Minimum Payments in 2025 | 131.4 | [2]
Minimum Payments in 2026 | 138.3 | [2]
Minimum Payments Thereafter | 1,060.6 | [2]
Long-Term Service Agreements [Member] |  |
Minimum Annual Payments for Certain Long-Term Commitments [Line Items] |  |
Minimum Payments in 2022 | 58.9 | [3]
Minimum Payments in 2023 | 22.5 | [3]
Minimum Payments in 2024 | 23.1 | [3]
Minimum Payments in 2025 | 0.0 | [3]
Minimum Payments in 2026 | 0.0 | [3]
Minimum Payments Thereafter | $ 0.0 | [3]
[1] | Easement obligations represent the minimum payments for our land easement agreements at our wind energy facilities.
[2] | Does not include the agreement with Manitoba Hydro expiring in 2022, as this contract is for surplus energy only; or the Oliver Wind I, Oliver Wind II or Nobles 2 PPAs, as Minnesota Power only pays for energy as it is delivered. (See Power Purchase Agreements.)
[3] | Consists of long-term service agreements for wind energy facilities and minimum purchase commitments under coal and rail contracts.

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- Definition Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308 + Details
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- Definition Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308 + Details
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- Definition Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308 + Details
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- Definition Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308 + Details
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- Definition Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308 + Details
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