Condensed Consolidated Statements of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2018	$ 827,373	$ 541,762	$ 303,490	$ (17,879)
Beginning balance (in shares) at Dec. 31, 2018		30,417,223
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	22,726		22,726
Other comprehensive income (loss)	8,952			8,952
Stock options exercised	647	$ 647
Stock options exercised (in shares)		41,000
RSU vesting	278	$ 278
PSU vesting	119	$ 119
RSUs released	0
RSUs released (in shares)		355
PSUs released	0
PSUs released (in shares)		0
Repurchase of common stock	(1,035)	$ (466)	(569)
Repurchase of common stock (in shares)		(26,159)
Dividends paid	(5,782)		(5,782)
Ending balance at Mar. 31, 2019	853,278	$ 542,340	319,865	(8,927)
Ending balance (in shares) at Mar. 31, 2019		30,432,419
Beginning balance at Dec. 31, 2019	$ 906,570	$ 543,998	367,794	(5,222)
Beginning balance (in shares) at Dec. 31, 2019	30,523,824	30,523,824
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 16,121		16,121
Other comprehensive income (loss)	(19,910)			(19,910)
Stock options exercised	$ 148	$ 148
Stock options exercised (in shares)	8,000	8,000
RSU vesting	$ 297	$ 297
PSU vesting	142	$ 142
RSUs released	0
RSUs released (in shares)		362
PSUs released	0
PSUs released (in shares)		0
Repurchase of common stock	(17,295)	$ (9,962)	(7,333)
Repurchase of common stock (in shares)		(558,670)
Dividends paid	(6,664)		(6,664)
Ending balance at Mar. 31, 2020	$ 866,426	$ 534,623	$ 356,935	$ (25,132)
Ending balance (in shares) at Mar. 31, 2020	29,973,516	29,973,516