Certain Financial Statement Information Interest Income/Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Schedule of Interest Income, Net
Interest income	$ 388	$ 402	$ 729	$ 870
Net realized gain on short-term investments	5	86	0	3,284
Interest income, net	$ 393	$ 488	$ 729	$ 4,154