Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reconciliation of Federal Statutory to Actual Tax Expense:
Federal statutory income tax at 21%	$ 10,249	$ 9,995	$ 19,858	$ 19,086
Tax-exempt interest income	(2,403)	(2,045)	(4,670)	(4,060)
Share-based compensation	(41)	(91)	(391)	(532)
Tax-exempt earnings and gains on life insurance	(199)	(211)	(406)	(458)
Tax credits	(63)	(62)	(141)	(23)
Other	206	375	440	559
Actual Tax Expense	$ 7,749	$ 7,961	$ 14,690	$ 14,572
Federal statutory income tax rate	21.00%	21.00%
Effective Tax Rate	15.90%	16.70%	15.50%	16.00%

Percentage 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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