Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 19,867	$ 22,469	$ 49,081	$ 60,748
Other comprehensive income (loss):
Foreign currency translation adjustments	(9,013)	6,283	(3,176)	(1,740)
Unrealized gain (loss) on investments, net of tax	(156)	543	598	791
Other	546	(30)	579	(29)
Comprehensive income	11,244	29,265	47,082	59,770
Foreign currency translation adjustments	(5,947)		(5,947)		(2,771)
Unrealized loss on investments, net of tax	(3,255)		(3,255)		(3,853)
Other	241		241		(338)
Accumulated other comprehensive loss	$ (8,961)		$ (8,961)		$ (6,962)