CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net loss	$ (41,786)	$ (5,502)	$ (81,618)	$ (20,863)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	155	(180)	489	32
Unrealized gain (loss) on short-term investments, net of tax	(235)	254	(136)	134
Other comprehensive income (loss), net of tax	(80)	74	353	166
Total comprehensive loss, net of tax	$ (41,866)	$ (5,428)	$ (81,265)	$ (20,697)