Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 18,638	$ 18,980	$ 35,171	$ 40,153
Other comprehensive income
Unrealized (loss) gain on debt securities (net of tax expense of $11 and $709 in 2020, and net of tax expense of $260 and $434 in 2019, respectively)	(44)	915	2,105	1,559
Accretion of unrealized loss on debt securities reclassified to held-to-maturity (net of tax expense of $76 and $160 in 2020, and net of tax expense of $85 and $171 in 2019, respectively)	113	123	228	248
Unrealized gain on cash flow hedge (net of tax expense of $173)	547	0	0	0
Total other comprehensive income	616	1,038	2,333	1,807
Total comprehensive income	$ 19,254	$ 20,018	$ 37,504	$ 41,960