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Significant Accounting Policies Income Taxes (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Significant Accounting Policies [Abstract] |  |
PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained | 50.00% |
Valuation Allowance Against Any Deferred Tax Asset | $ 0 | $ 0

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- Definition Valuation Allowance Against Any Deferred Tax Asset + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration