CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS [Abstract]
Net loss	$ (28,161)	$ (10,233)	$ (23,909)
Other comprehensive income (loss), net of tax [Abstract]
Foreign currency translation adjustment	79	415	284
Unrealized gains (losses) on available-for-sale and non-marketable securities	2,271	(4,093)	6,979
Reclassification adjustment for realized (losses) gains recognized in net loss	2,060	(1,003)	916
Unrealized gains on cash flow hedges	826	0	0
Net change in other comprehensive income (loss), net of tax	1,116	(2,675)	6,347
Comprehensive loss	$ (27,045)	$ (12,908)	$ (17,562)