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v3.20.2

Income Taxes State Audits (Details) | 9 Months Ended
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Sep. 30, 2020 USD ($)
WISCONSIN |
Income Tax Examination [Line Items] |
Potential Tax Adjustments | $ 0
NSP Minnesota [Member] |
Income Tax Examination [Line Items] |
Potential Tax Adjustments | $ 0

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- Definition The potential income tax expense that could become payable in the event of a successful challenge by a taxing authority of an entity's income tax position. + References No definition available. + Details
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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Period Type: |