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Federal Income Taxes (Reconciliation of the provision for federal income taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory tax rate	21.00%	21.00%	34.00%
Income taxes at 34% statutory rate	$ 3,025	$ 3,231	$ 5,526
Interest income on tax exempt municipal securities	(990)	(1,106)	(1,889)
Earnings on corporate owned life insurance policies	(160)	(148)	(247)
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	0	0	319
Other	283	231	34
Total effect of nontaxable income	(867)	(1,023)	(1,783)
Effect of nondeductible expenses	108	113	149
Effect of tax credits	(984)	(958)	(876)
Unrecognized Deferred Tax Benefit on Joint Venture Investment	98	0	0
Federal income tax expense	$ 1,380	$ 1,363	$ 3,016

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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