CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (8,947)	$ (18,326)	$ (20,844)	$ (37,065)
Other comprehensive (loss) income:
Net unrealized loss on available-for-sale securities	(31)	(35)	(53)	(6)
Foreign currency translation adjustments				16
Other comprehensive (loss) income	(31)	(35)	(53)	10
Comprehensive loss	$ (8,978)	$ (18,361)	$ (20,897)	$ (37,055)