Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Reconciliation of Federal Statutory to Actual Tax Expense:
Federal statutory income tax rate	35.00%	35.00%
Federal statutory income tax at 35%	$ 8,143	$ 7,702
Tax-exempt interest income	(2,026)	(1,429)
Stock compensation	5	8
Earnings on life insurance	(517)	(262)
Tax credits	(129)	(144)
Other	98	(41)
Actual Tax Expense	$ 5,574	$ 5,834
Effective Tax Rate	24.00%	26.50%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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 other deductions.

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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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