Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Common Stock in Treasury	Retained Earnings	Accumulated Other Comprehensive Loss	Other Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common shares beginning balance (in shares)		20,646
Treasury Stock, Common, Shares			6,502
Stockholders' Equity Attributable to Parent	$ 885,053	$ 309,492	$ (237,746)	$ 854,334	$ (46,948)	$ 5,921
Net income	13,409			13,409
Other comprehensive loss	(2,373)				(2,373)
Cash dividends declared	(2,692)			(2,692)
Stock-based compensation activity (in shares)		(130)	(130)
Stock-based compensation activity	2,495	$ 14,969	$ (12,461)	(13)
Payments of withholding taxes for stock-based compensation awards (in shares)		(45)	(45)
Payments of withholding taxes for stock-based compensation awards	(6,013)		$ (6,013)
Directors' deferred compensation (in shares)		0	0
Directors’ deferred compensation	44	$ 31	$ (48)			61
Common shares beginning balance (in shares)		20,731
Treasury Stock, Common, Shares			6,417
Stockholders' Equity Attributable to Parent	889,923	$ 324,492	$ (256,268)	865,038	(49,321)	5,982
Common shares beginning balance (in shares)		20,764
Treasury Stock, Common, Shares			6,384
Stockholders' Equity Attributable to Parent	868,881	$ 336,136	$ (261,880)	849,111	(61,046)	6,560
Net income	17,698			17,698
Other comprehensive loss	3,347				3,347
Cash dividends declared	(2,803)			(2,803)
Stock-based compensation activity (in shares)		(75)	(75)
Stock-based compensation activity	2,986	$ 6,597	$ (3,607)	(4)
Payments of withholding taxes for stock-based compensation awards (in shares)		(25)	(25)
Payments of withholding taxes for stock-based compensation awards	(2,224)		$ (2,224)
Directors’ deferred compensation	44	$ 26	$ (45)			63
Common shares beginning balance (in shares)		20,814
Treasury Stock, Common, Shares			6,334
Stockholders' Equity Attributable to Parent	$ 887,929	$ 342,759	$ (267,756)	$ 864,002	$ (57,699)	$ 6,623