Condensed Consolidated Statement of Shareholders' Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock, At Cost [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balances at Dec. 31, 2011	$ 389	$ 180,538	$ (30,520)	$ 307,934	$ (4,049)	$ 454,292
Balances (in shares) at Dec. 31, 2011	36,399
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense		3,260
Issuance of restricted stock		(209)	335
Issuance of restricted stock (in shares)	27
Exercise of stock options		(1,015)	1,356
Exercise of stock options (in shares)	105
Surrender of fully vested options		(497)
Income tax benefit on stock-based compensation		550
Change in cumulative translation adjustment					4,055	4,055
Net income				18,772		18,772
Balances at Sep. 30, 2012	$ 389	$ 182,627	$ (28,829)	$ 326,706	$ 6	$ 480,899
Balances (in shares) at Sep. 30, 2012	36,531