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Commitments and Contingencies (Details) - Otter Tail Power Company $ in Millions | Jun. 23, 2022 USD ($) MWh | Sep. 30, 2022 USD ($)
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Other Commitments [Line Items] |  |
Option exercised | MWh | 62.4 |
Payments to acquire wind farm | $ 49.7 |
Federal Energy Regulatory Commission |  |
Other Commitments [Line Items] |  |
Estimated liability of refund obligation |  | $ 2.5

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- Definition Derivative, Nonmonetary, Energy Measure + References No definition available. + Details
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Period Type: | duration

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- Definition This element represents amount of estimated liability for FERC ordered MISO tariff ROE refund obligation. + References No definition available. + Details
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- Definition Payments To Acquire Wind Farm + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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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. + Details
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- Details
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Namespace Prefix: |
Data Type: | na
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- Details
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