Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (32,695)	$ (16,431)	$ (58,762)	$ (30,125)
Comprehensive loss
Unrealized loss on investments	(94)		(42)
Foreign currency translation adjustments	(68)		(73)
Comprehensive loss	$ (32,857)	$ (16,431)	$ (58,877)	$ (30,125)