Significant Customer and Geographic Information - Revenue by Geographical Location (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 41,779	$ 39,743	$ 83,277	$ 77,556
United States of America
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	25,025	20,519	43,264	38,563
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	6,700	5,014	12,451	12,406
Hong Kong
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	6,663	6,115	16,005	12,086
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	1,392	4,373	5,238	8,186
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	335	1,370	2,985	2,684
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 1,664	$ 2,352	$ 3,334	$ 3,631