CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 82,414	$ 68,051	$ 57,786
Other comprehensive loss:
Unrealized depreciation of investment securities available-for-sale	(9,073)	(3,147)	(6,547)
Reclassification adjustment for realized losses (gains) included in net income	345	(4,340)	(1,796)
Income tax effect	2,102	2,811	3,132
Other comprehensive loss, net of tax	(6,626)	(4,676)	(5,211)
Comprehensive income	75,788	63,375	52,575
Comprehensive (income) loss attributable to noncontrolling interests	0	0	0
Comprehensive income available to common shareholders	$ 75,788	$ 63,375	$ 52,575

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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