Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Statutory Rate applied to the pre-tax income	35.00%	35.00%	35.00%
Statutory Rate Times Pre-tax Income	$ 14,145	$ 12,907	$ 12,153
Add (Subtract) the Tax Effect of:
Income from Tax-exempt Loans and Investments	(1,697)	(1,157)	(1,007)
State Income Tax, Net of Federal Tax Effect	625	826	494
General Business Tax Credits	(562)	(556)	(547)
Company Owned Life Insurance	(289)	(338)	(341)
Gain on United Commerce Bancorp Stock	0	(120)	0
Other Differences	(153)	(98)	(83)
Total Income Taxes	$ 12,069us-gaap_IncomeTaxExpenseBenefit	$ 11,464us-gaap_IncomeTaxExpenseBenefit	$ 10,669us-gaap_IncomeTaxExpenseBenefit

Income Tax Reconciliation Deductions Gain On Bancorp Stock One

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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 life insurance expense.

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