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Stockholders' Equity (Details) - USD ($) $ in Thousands |  |  | 9 Months Ended |
--- | --- | --- | --- | ---
May 03, 2021 | Jul. 15, 2020 | Sep. 30, 2021 | Dec. 31, 2020
Class of Stock [Line Items] |  |  |  |
Total capitalization |  |  | $ 1,547,101 | $ 1,495,398
Otter Tail Power Company |  |  |  |
Class of Stock [Line Items] |  |  |  |
Equity to total capitalization ratio |  |  | 52.60% |
Net assets restricted from distribution |  |  | $ 674,900 |
Minimum | Otter Tail Power Company | Minnesota Public Utilities Commission |  |  |  |
Class of Stock [Line Items] |  |  |  |
Public utilities, requested equity capital structure, percentage |  | 47.50% |  |
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 |  | 58.10% |  |
Second Shelf Registration |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shelf registration (in shares) | 1,500,000 |  |  |

X
- Definition Represents the ratio of Equity to total capitalization, which includes as equity minority interest and preferred stock as well as all of the components of common equity as presented on the balance sheet. Total capitalization is calculated as equity plus short-term debt plus long-term debt as presented on the balance sheet. + References No definition available. + Details
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- Definition This element represents the total consolidated (as applicable) capitalization of the entity which is comprised of its long-term debt and equity instruments. The table may be detailed by subsidiary (legal entity) and include information by type of debt or equity detailed by instrument. + References No definition available. + Details
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- Definition Percentage of public utility's requested equity to capital, including debt and equity. + References No definition available. + Details
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- Details
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