Schedule of Tax Effects Allocated to Each Component of Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Components Of Other Comprehensive Income Loss [Line Items]
Foreign currency translation adjustment	$ (19,875)	$ (9,214)
Unrealized gain on cash flow hedging instruments	2,227
Income tax expense	(601)
Unrealized gain on cash flow hedging instruments, net of tax	1,626
Reclassification of gain on cash flow hedging instruments into earnings	(188)
Income tax expense	51
Reclassification of gain on cash flow hedging instruments into earnings, net of tax	(137)
Unrealized gain on available-for-sale securities	11	2
Income tax expense	(4)	(1)
Unrealized gain on available-for-sale securities, net of tax	7	1
Other comprehensive loss	$ (18,379)	$ (9,213)

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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