CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss	Total
Balances at Dec. 31, 2013	$ 275	$ 296,133	$ 296,735	$ (57,770)	$ (14,912)	$ 520,461
Balances (in shares) at Dec. 31, 2013	27,507			1,678
Increase (Decrease) in Stockholders' Equity
Net income			46,177			46,177
Other comprehensive loss, net of tax					(8,567)	(8,567)
Issuance of common stock under share-based compensation plans	$ 2	1,032				1,034
Issuance of common stock under share-based compensation plans (in shares)	215
Tax effect of share-based compensation plans		(1,118)				(1,118)
Share-based compensation expense		6,998				6,998
Dividends declared on common stock			(4,102)			(4,102)
Balances at Dec. 31, 2014	$ 277	303,045	338,810	$ (57,770)	(23,479)	560,883
Balances (in shares) at Dec. 31, 2014	27,722			1,678
Increase (Decrease) in Stockholders' Equity
Net income			44,854			44,854
Other comprehensive loss, net of tax					(4,017)	(4,017)
Issuance of common stock under share-based compensation plans	$ 2	(2)
Issuance of common stock under share-based compensation plans (in shares)	216
Tax effect of share-based compensation plans		(1,419)				(1,419)
Share-based compensation expense		8,029				8,029
Purchase of treasury stock				$ (12,765)		(12,765)
Purchase of treasury stock (in shares)				402
Dividends declared on common stock			(6,837)			(6,837)
Balances at Dec. 31, 2015	$ 279	309,653	376,827	$ (70,535)	(27,496)	588,728
Balances (in shares) at Dec. 31, 2015	27,938			2,080
Increase (Decrease) in Stockholders' Equity
Net income			18,652			18,652
Other comprehensive loss, net of tax					4,079	4,079
Issuance of common stock under share-based compensation plans	$ 3	(3)
Issuance of common stock under share-based compensation plans (in shares)	236
Tax effect of share-based compensation plans		(2,322)				(2,322)
Share-based compensation expense		7,588				7,588
Purchase of treasury stock				$ (9,510)		(9,510)
Purchase of treasury stock (in shares)				485
Dividends declared on common stock			(8,318)			(8,318)
Balances at Dec. 31, 2016	$ 282	$ 314,916	$ 387,161	$ (80,045)	$ (23,417)	$ 598,897
Balances (in shares) at Dec. 31, 2016	28,174			2,565