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Federal Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Income Tax Disclosure [Abstract] |  |  |  |
Federal statutory tax rate | 21.00% | 21.00% | 21.00% | 21.00%
Income taxes at 34% statutory rate | $ 1,069 | $ 1,065 | $ 2,752 | $ 2,866
Interest income on tax exempt municipal securities | (176) | (224) | (570) | (704)
Earnings on corporate owned life insurance policies | (40) | (39) | (301) | (118)
Other | (4) | (4) | (12) | (12)
Total effect of nontaxable income | (220) | (267) | (883) | (834)
Effect of nondeductible expenses | 7 | 14 | 14 | 27
Effective Income Tax Rate Reconciliation, Tax Credit, Amount | 122 | 182 | 388 | 539
Federal income tax expense | $ 734 | $ 630 | $ 1,495 | $ 1,520

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