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Borrowings - Schedule of Available Unused Lines of Credit (Parenthetical) (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
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Debt Disclosure [Abstract] |  |
Federal Home Loan Bank, advances, general debt obligations, disclosures, collateral pledged | $ 59.0 | $ 36.1
Collateral exposure with FHLB in form of advances | 40.0 | 20.0
Collateral pledged in excess available to utilize additional credit | $ 19.0 | $ 16.1

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- Definition Amount of collateral pledged in excess available to utilize additional credit. + References No definition available. + Details
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- Definition Amount of advances from the Federal Home Loan Bank (FHLB). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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- Definition Amount of the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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