Consolidated Statements of Comprehensive Loss (Unaudited) - 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	$ (8,580)	$ (9,984)	$ (16,928)	$ (20,878)
Other comprehensive income (loss):
Unrealized gain (loss) on investments, net of tax	4	93	10	(63)
Unrealized gain on currency translation				1
Other comprehensive income (loss)	4	93	10	(62)
Comprehensive loss	$ (8,576)	$ (9,891)	$ (16,918)	$ (20,940)