Condensed Consolidated Statements of Comprehensive Loss (unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net loss		$ (4,640)	$ (8,061)	$ (15,179)	$ (15,465)
Other comprehensive loss, net of tax:
Unrealized gain (loss) on investments	[1]	(30)	(196)	117	(1,849)
Gain (loss) on foreign currency translation		26	(233)	(119)	(370)
Other comprehensive loss, net of tax		(4)	(429)	(2)	(2,219)
Total comprehensive loss		(4,644)	(8,490)	(15,181)	(17,684)
Other comprehensive income: reclassification adjustments [Abstract]
OCI, Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax		$ 22	$ 137	$ 50	$ 1,498

[1] The amounts reclassified from accumulated other comprehensive loss and recorded in realized gain on short-term investments and interest income, net in the Condensed Consolidated Statement of Operations related to the sale of short-term investments were $22,000 and $137,000 for the three months ended September 30, 2016 and 2015, respectively, and $50,000 and $1,498,000 for the six months ended September 30, 2016 and 2015, respectively. Refer to Note 2, Certain Financial Statement Information, to the Condensed Consolidated Financial Statements for additional details.