Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 22,251	$ 11,955	$ 43,172	$ 24,346
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on investment securities arising during the period, net of income tax expense (benefit) for three months of $(333) and $921, and for six months of $($2,598) and $1,268, respectively	(1,017)	1,502	(7,921)	2,070
Less: Reclassification adjustment for realized gains on sale of securities available for sale included in net income, net of income tax expense for the six months of $2 and $0, respectively	0	0	(7)	0
Total other comprehensive income (loss)	(1,017)	1,502	(7,928)	2,070
Total comprehensive income	$ 21,234	$ 13,457	$ 35,244	$ 26,416