Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 376,913	$ 261,988	$ 161,441
Other comprehensive income (loss)
Net unrealized holding gains (losses) arising during period on investment securities available-for-sale, net of tax expense (benefit) of ($4,762), $4,084 and $6,211	(17,915)	15,363	23,365
Reclassification adjustment for gains on investment securities included in earnings, net of tax of $—, $— and $12	0	0	(46)
Net unrealized gains (losses) on cash flow hedge during the period, net of tax expense (benefit) of $—, $39 and ($133)	0	147	(498)
Total other comprehensive income (loss)	(17,915)	15,510	22,821
Comprehensive income	$ 358,998	$ 277,498	$ 184,262