Effective Income Tax Rate Reconciliation, Bank Owned Life Insurance Earnings, Amount

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Effective Income Tax Rate Reconciliation, Deduction, Share-based Compensation, Amount

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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 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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Income Tax - Reconciliation of Federal Statutory to Actual Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal statutory income tax rate									21.00%	35.00%	35.00%
Federal Statutory Income Tax at 21% for 2018 and 35% for 2017 and 2016									$ 39,509	$ 46,758	$ 38,031
Tax-exempt Interest Income									(8,347)	(11,127)	(8,749)
Stock Compensation									(622)	(893)	(61)
Earnings on Life Insurance									(868)	(2,302)	(1,486)
Tax Credits									(615)	(811)	(564)
Tax Cuts and Jobs Act - Rate Reform Impact										5,120
Other									(58)	779	438
Income Tax Expense	$ 5,949	$ 8,478	$ 7,961	$ 6,611	$ 15,210	$ 7,939	$ 7,207	$ 7,168	$ 28,999	$ 37,524	$ 27,609
Effective Tax Rate									15.40%	28.10%	25.40%