Federal Income Taxes (Reconciliation of the provision for federal income taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal statutory tax rate	21.00%	21.00%	21.00%
Income taxes at 34% statutory rate	$ 2,493	$ 3,025	$ 3,231
Interest income on tax exempt municipal securities	(802)	(990)	(1,106)
Earnings on corporate owned life insurance policies	(346)	(160)	(148)
Other	288	283	231
Total effect of nontaxable income	(860)	(867)	(1,023)
Effect of nondeductible expenses	68	108	113
Effect of tax credits	(830)	(984)	(958)
Unrecognized Deferred Tax Benefit on Joint Venture Investment	116	98	0
Federal income tax expense	$ 987	$ 1,380	$ 1,363

Effective Income Tax Rate Reconciliation, Tax Exempt Income And Tax Credits, Amount

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

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses.

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