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Significant Accounting Policies Cash Equivalents (Details) | 12 Months Ended
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Dec. 31, 2019
Cash and Cash Equivalents [Abstract] |
Maturity of Federal Funds Sold Considered Cash Equivalents | 1 day
Maturity of Resell Agreement Considered Cash Equivalents, Minimum | 1 day
Maturity of Resell Agreements Considered Cash Equivalents, Maximum | 30 days

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- Definition Maturity of Resell Agreement Considered Cash Equivalents, Minimum + References No definition available. + Details
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- Definition Maturity of Resell Agreements Considered Cash Equivalents, Maximum + References No definition available. + Details
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