Consolidated Statement of Shareholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulative Other Comprehensive Income (Loss) [Member]	Retained Income (Deficit) [Member]
Balance at Dec. 31, 2010		$ 21,486	$ 281,376	$ 10,164	$ (101,221)
Balance, shares at Dec. 31, 2010		35,315,732
Stockholders' Equity [Roll Forward]
Net income	24,505				24,505
Sales under option plans, shares	59,031	59,031
Sales under option plans		36	597
Dividend reinvestment plan, shares		11,610
Dividend reinvestment plan		7	111
Restricted stock and stock option grants, net (shares)		28,750
Restricted stock and stock option grants, net			2,595
Foreign currency translation adjustment	(2,240)			(2,240)
Purchase for treasury, shares		(2,000,000)
Purchases for treasury		(1,220)	(19,726)
Stock contribution, shares		5,365
Stock contribution		3	47
Declared dividends					(9,750)
Pension liability, net of tax	(630)			(630)
Balance at Dec. 31, 2011		20,312	265,000	7,294	(86,466)
Balance, shares at Dec. 31, 2011		33,420,488
Stockholders' Equity [Roll Forward]
Net income	29,962				29,962
Sales under option plans, shares	288,794	278,659
Sales under option plans		145	2,870
Dividend reinvestment plan, shares		7,112
Dividend reinvestment plan		5	102
Restricted stock vested, shares		40,500
Restricted stock award		24	(24)
Restricted stock and stock option grants, net (shares)		11,484
Restricted stock and stock option grants, net			2,708
Cancellations and terminations of share grants			(253)
Foreign currency translation adjustment	2,791			2,791
Purchase for treasury, shares		(281,797)
Purchases for treasury		(172)	(4,032)
Stock contribution, shares		3,743
Stock contribution		2	48
Declared dividends					(10,852)
Pension liability, net of tax	558			558
Balance at Dec. 31, 2012	230,022	20,316	266,419	10,643	(67,356)
Balance, shares at Dec. 31, 2012		33,480,189
Stockholders' Equity [Roll Forward]
Net income	26,002				26,002
Sales under option plans, shares	503,321	503,321
Sales under option plans		299	5,394
Dividend reinvestment plan, shares		7,390
Dividend reinvestment plan		4	109
Restricted stock vested, shares		112,000
Restricted stock and stock option grants, net (shares)		33,152
Restricted stock and stock option grants, net			2,237
Cancellations and terminations of share grants			389
Foreign currency translation adjustment	(9,292)			(9,292)
Purchase for treasury, shares		(530,983)
Purchases for treasury		(314)	(7,782)
Stock contribution, shares		12,682
Stock contribution		8	194
Shares withheld for employee taxes on equity awards, shares		(44,973)
Shares withheld for employee taxes on equity awards			(684)
Declared dividends					(12,155)
Pension liability, net of tax	1,076			1,076
Balance at Dec. 31, 2013	$ 235,507	$ 20,313	$ 266,276	$ 2,427	$ (53,509)
Balance, shares at Dec. 31, 2013		33,572,778