Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reconciliation of Federal Statutory to Actual Tax Expense:
Federal statutory income tax rate	35.00%	35.00%	35.00%	35.00%
Federal statutory income tax at 35%	$ 9,353	$ 9,389	$ 17,496	$ 17,091
Tax-exempt interest income	(2,104)	(1,738)	(4,130)	(3,167)
Basis difference on sale of insurance subsidiary		2,252		2,252
Stock compensation	8	10	13	18
Earnings on life insurance	(453)	(223)	(970)	(485)
Tax credits	(129)	(148)	(258)	(292)
Other	41	(686)	139	(727)
Actual Tax Expense	$ 6,716	$ 8,856	$ 12,290	$ 14,690
Effective Tax Rate	25.10%	33.00%	24.60%	30.10%

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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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