Federal Home Loan Bank Advances (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2020
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank advances outstanding		$ 640.0
Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances [Line Items]
Additional borrowings possible		$ 3,400.0
FHLB advances paid-off prior to maturity date	$ 315.0
Federal Home Loan Bank Advances \| Weighted Average
Federal Home Loan Bank, Advances [Line Items]
Weighed average contractual interest rate		1.57%

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Federal Home Loan Bank advances having varying put dates

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