Condensed Conslidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Statement of Income and Comprehensive Income [Abstract]
Net loss	$ (10,563)	$ (9,150)
Other comprehensive income:
Foreign currency translation loss	(7)	(3)
Unrealized gains on securities:
Unrealized holding gains arising during period	99	36
Other comprehensive income	92	33
Comprehensive loss	$ (10,471)	$ (9,117)