Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory Rate applied to the pre-tax income	35.00%	35.00%	35.00%
Statutory Rate Times Pre-tax Income	$ 18,274	$ 17,195	$ 14,585
Add (Subtract) the Tax Effect of:
Income from Tax-exempt Loans and Investments	(3,304)	(2,929)	(2,250)
State Income Tax, Net of Federal Tax Effect	505	564	727
General Business Tax Credits	(715)	(621)	(750)
Company Owned Life Insurance	(469)	(346)	(296)
Revaluation of Deferred Tax Assets/Liabilities due to Tax Reform	(2,284)
Other Differences	(473)	83	(410)
Total Income Taxes	$ 11,534	$ 13,946	$ 11,606

Effective Income Tax Rate Reconciliation, Non-taxable Company Owned Life Insurance, Net, 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 increase (decrease) in the income tax rates.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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