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Federal Home Loan Bank and Federal Reserve Bank Borrowings (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Federal Home Loan Bank and Federal Reserve Bank Borrowings [Abstract] |  |  |
FHLB Borrowing Capacity | $ 2,090,000 | $ 1,960,000 |
FHLB Fixed Rate Advances, Total Amount before valuation adjustment | $ 7,000 | 953,000 |
Paycheck Protection Program Liquidity Facility (PPPLF) borrowing rate | 0.35% |  |
Federal Reserve Bank, Average balance during the year | $ 1,100 | 99 | $ 14
Federal Reserve Bank borrowing capacity | $ 234,400 | $ 209,100 |

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- Definition Federal Home Loan Bank, Advances, Maturities Summary by Interest Rate Type, Fixed Rate, Before Valuation Adjustment + References No definition available. + Details
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- Definition Federal Home Loan Bank and Federal Reserve Bank Borrowings [Abstract] + References No definition available. + Details
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- Definition Federal Reserve Bank, Advances, Activity for the year, average balance of agreements outstanding + References No definition available. + Details
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- Definition Federal Reserve Bank, Advances, Maximum Amount Available + References No definition available. + Details
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- Definition Paycheck Protection Program Liquidity Facility (PPPLF) borrowing rate + References No definition available. + Details
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- Definition Amount of maximum advances or credit lines available 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 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22 (b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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