Federal Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Federal statutory tax rate	34.00%	34.00%	34.00%	34.00%
Income taxes at 34% statutory rate	$ 1,381	$ 1,725	$ 2,555	$ 3,236
Interest income on tax exempt municipal securities	(486)	(510)	(988)	(1,010)
Earnings on corporate owned life insurance policies	(66)	(66)	(130)	(130)
Effect of tax credits	(193)	(181)	(387)	(367)
Other	(18)	(26)	(36)	(52)
Total effect of nontaxable income	(763)	(783)	(1,541)	(1,559)
Effect of nondeductible expenses	37	35	78	71
Federal income tax expense	$ 655	$ 977	$ 1,092	$ 1,748

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

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Corporate Owned Life Insurance, Amount

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Municipal Securities, Amount

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Other, 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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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from 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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