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Stockholders' Equity (Details) - USD ($) $ in Thousands |  |  | 6 Months Ended |
--- | --- | --- | --- | ---
Jan. 26, 2022 | May 03, 2021 | Jun. 30, 2022 | Dec. 31, 2021
Class of Stock [Line Items] |  |  |  |
Total capitalization |  |  | $ 1,940,242 | $ 1,724,791
Otter Tail Power Company |  |  |  |
Class of Stock [Line Items] |  |  |  |
Equity to total capitalization ratio |  |  | 52.20% |
Net assets restricted from distribution |  |  | $ 714,400 |
Minimum | Otter Tail Power Company | Minnesota Public Utilities Commission |  |  |  |
Class of Stock [Line Items] |  |  |  |
Public utilities, requested equity capital structure, percentage | 48.00% |  |  |
Maximum | Otter Tail Power Company |  |  |  |
Class of Stock [Line Items] |  |  |  |
Total capitalization |  |  | $ 1,700,000 |
Maximum | Otter Tail Power Company | Minnesota Public Utilities Commission |  |  |  |
Class of Stock [Line Items] |  |  |  |
Public utilities, requested equity capital structure, percentage | 58.70% |  |  |
Second Shelf Registration |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shelf registration (in shares) |  | 1,500,000 |  |
Number of shares issued (in shares) |  |  | 70,369 |
Number of shares available for grant (in shares) |  |  | 1,314,451 |

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- Details
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