Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net income	$ 19,584	$ 12,445	$ 39,166	$ 32,556
Securities available for sale
Unrealized gains arising during period	2,675	1,567	12,599	10,851
Change in unrealized gains and losses for which a portion of other than temporary impairment has been recognized in earnings	15	(53)	(66)	(55)
Reclassification adjustments for gains included in earnings	0	0	(253)	(137)
Unrealized gains recognized in other comprehensive income on securities available for sale	2,690	1,514	12,280	10,659
Income tax expense	565	318	2,579	2,238
Unrealized gains recognized in other comprehensive income on securities available for sale, net of tax	2,125	1,196	9,701	8,421
Derivative instruments
Unrealized loss arising during period	(26)	(72)	(354)	(1,740)
Reclassification adjustment for (income) expense recognized in earnings	310	(102)	646	(393)
Unrealized gains (losses) recognized in other comprehensive income on derivative instruments	284	(174)	292	(2,133)
Income tax expense (benefit)	59	(36)	61	(447)
Unrealized gains (losses) recognized in other comprehensive income on derivative instruments, net of tax	225	(138)	231	(1,686)
Other comprehensive income	2,350	1,058	9,932	6,735
Comprehensive income	$ 21,934	$ 13,503	$ 49,098	$ 39,291