CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]
Net loss	$ (10,474)	$ (15,437)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustment	151	(3,125)
Unrealized change in available-for-sale and non-marketable securities	1,319	(275)
Unrealized change in cash flow hedges	297	1,086
Net change in other comprehensive (loss) income, net of tax	1,767	(2,314)
Comprehensive loss	$ (8,707)	$ (17,751)