Income Taxes - Reconciliation between applicable income taxes and statutory federal tax rate (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Tax amount
Taxes at statutory federal income tax rate	$ 4,894	$ 1,982	$ 9,491	$ 6,114
Tax effect of tax exempt income	(134)	(107)	(382)	(329)
Tax effect of other	888	457	1,589	1,440
Total income tax expense	$ 5,648	$ 2,332	$ 10,698	$ 7,225
Percentage of pretax income
Taxes at statutory federal income tax rate (as percentage)	21.00%	21.00%	21.00%	21.00%
Tax effect of tax exempt income (as percentage)	(0.60%)	(1.10%)	(0.80%)	(1.10%)
Tax effect of other (as percentage)	3.80%	4.80%	3.50%	4.90%
Applicable income taxes (as percentage)	24.20%	24.70%	23.70%	24.80%

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

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