Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Common stock [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Treasury stock [Member]	Accumulated other comprehensive income, net [Member]	Total
Balance in the beginning at Dec. 31, 2013	$ 512	$ 990,216	$ 39,966	$ (126,146)	$ (6,756)	$ 897,792
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			9,176			9,176
Stock-based compensation		3,572				3,572
Issuance under equity compensation plan, including tax benefit and gain on reissuance of treasury stock		(576)				(576)
Repurchase of shares				(119,370)		(119,370)
Cash dividends declared			(8,614)			(8,614)
Other comprehensive income (loss)					12,595	12,595
Balance in the ending at Dec. 31, 2014	512	993,212	40,528	(245,516)	5,839	794,575
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			4,881			4,881
Stock-based compensation		3,349				3,349
Issuance under equity compensation plan, including tax benefit and gain on reissuance of treasury stock	1	(1,701)		904		(796)
Repurchase of shares				(175,048)		(175,048)
Cash dividends declared			(6,739)			(6,739)
Warrant reclassification		3,066				3,066
Other comprehensive income (loss)					(5,744)	(5,744)
Balance in the ending at Dec. 31, 2015	513	997,926	38,670	(419,660)	95	617,544
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			23,060			23,060
Stock-based compensation		3,492				3,492
Issuance of stock under equity compensation and ASPP plans, including gain on reissuance of treasury stock	1	(13,790)		7,588		(6,201)
Repurchase of shares				(93,573)		(93,573)
Cash dividends declared			(6,276)			(6,276)
Warrant exercise		(3,541)		3,541
Other comprehensive income (loss)					(1,857)	(1,857)
Balance in the ending at Dec. 31, 2016	$ 514	$ 984,087	$ 55,454	$ (502,104)	$ (1,762)	$ 536,189