CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME [Abstract]
Net loss	$ (12,263)	$ (10,720)	$ (23,521)	$ (23,806)
Other comprehensive income:
Net change in unrealized loss on auction rate securities	60	0	68	8
Total other comprehensive income	60	0	68	8
Comprehensive loss	$ (12,203)	$ (10,720)	$ (23,453)	$ (23,798)