Borrowed Funds (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Interest payable	$ 806,000	$ 1,076,000
Federal home loan bank advances	2,400,000,000	2,300,000,000
Other borrowings	0	$ 0
Municipal Securities [Member]
Debt Instrument [Line Items]
Collateral amount	$ 3,000,000.0
Securities Sold Under Repurchase Agreements [Member]
Debt Instrument [Line Items]
Weighted average interest rate at year-end	0.05%	0.05%
Proceeds from securities sold	$ 10,710,000

Amount of assets pledged to secure a debt instrument.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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-Publisher FASB
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Amount of interest payable on debt, including, but not limited to, trade payables.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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The cash flow from investments sold under the agreement to repurchase such investment.

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