Condensed Consolidated Statements of Comprehensive Loss (Unaudited) (USD $)	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Net income (loss)	$ 10,857,000	$ (23,390,000)
Other comprehensive loss, net of $0 tax for 2013 and 2012:
Unrealized loss on investments	(4,529,000)	(501,000)
Loss on foreign currency translation	(189,000)	(118,000)
Other comprehensive loss, net of $0 tax for 2013 and 2012:	(4,718,000)	(619,000)
Total comprehensive income (loss)	6,139,000	(24,009,000)
Other comprehensive loss, income tax provision	0	0
Reclassification adjustment from AOCI to earnings, short term investments	$ 3,200,000	$ 1,000,000