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Commitments and Contingencies (Details) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2021 USD ($)
Pending Litigation | Westmoreland Arbitration |
Other Commitments [Line Items] |
Recovery sought | $ 5.5
Otter Tail Power Company | Coyote Station |
Other Commitments [Line Items] |
Ownership percentage | 35.00%
Otter Tail Power Company | Federal Energy Regulatory Commission |
Other Commitments [Line Items] |
Estimated liability of refund obligation | $ 3.0

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- Details
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- Details
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- Details
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