Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net loss	$ (141,447)	$ (162,141)	$ (116,389)
Other comprehensive income (loss), net:
Change in unrealized gain/loss on available-for-sale securities	228	(312)	(240)
Foreign currency translation adjustment	(11,545)	(6,908)	(3,155)
Other comprehensive loss	(11,317)	(7,220)	(3,395)
Total comprehensive loss	$ (152,764)	$ (169,361)	$ (119,784)