Federal Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Federal statutory tax rate	34.00%	34.00%	34.00%	34.00%
Income taxes at 34% statutory rate	$ 1,723	$ 1,309	$ 4,959	$ 4,072
Interest income on tax exempt municipal securities	(509)	(501)	(1,519)	(1,498)
Earnings on corporate owned life insurance policies	(64)	(62)	(194)	(189)
Effect of tax credits	(175)	(187)	(542)	(575)
Other	(18)	(158)	(70)	(235)
Total effect of nontaxable income	(766)	(908)	(2,325)	(2,497)
Effect of nondeductible expenses	45	43	116	121
Federal income tax expense	$ 1,002	$ 444	$ 2,750	$ 1,696

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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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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