CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 44,170	$ 36,497	$ 26,477
Unrealized losses on available for sale securities:
Unrealized losses arising during the period	(1,462)	(1,169)	(2,310)
Less: Reclassification adjustment for net losses/(gains) included in net income	288		(119)
Before tax	(1,174)	(1,169)	(2,429)
Tax effect	255	438	930
Net of tax	(919)	(731)	(1,499)
Unrealized (loss)/gain on cash flow hedge
Unrealized holding (loss)/gain	(328)	2,138	587
Reclassification adjustment for losses included in net income	(124)
Before tax	(452)	2,138	587
Tax effect	111	(873)	(240)
Net of tax	(341)	1,265	347
Total other comprehensive (loss)/income	(1,260)	534	(1,152)
Total comprehensive income	$ 42,910	$ 37,031	$ 25,325