Comprehensive Income (Detail) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net income	$ 48,729	$ 25,624	$ 96,039	$ 45,395
Other comprehensive income:
Foreign currency translation adjustments, net of tax benefit of $4,160 and $3,791 in 2011, and tax benefit of $448 and $586 in 2010	5,322	(3,979)	8,579	(4,311)
Reclassification of unrealized loss on available for sale securities to the income statement		769		769
Unrealized loss on available for sale securities, net of tax		(57)		(387)
Unrealized (loss) gain on derivative instruments, net of tax benefit of $701 and $1,956 in 2011 and tax of $2,694 and $2,266 in 2010	(1,138)	4,472	(3,289)	3,761
Comprehensive income	$ 52,913	$ 26,829	$ 101,329	$ 45,227