Certain Financial Statement Information - Property and Equipment (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2016	Mar. 31, 2016
Schedule of Property and equipment
Machinery and equipment	$ 39,946	$ 36,723
Leasehold improvements	7,528	7,529
Computers, office furniture and equipment	33,391	34,016
Property and equipment, gross	80,865	78,268
Less: accumulated depreciation	(68,136)	(64,975)
Property and equipment, net	$ 12,729	$ 13,293	[1]
Machinery and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	3 years
Machinery and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	5 years
Leasehold Improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	1 year
Leasehold Improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	5 years
Computers, Office Furniture and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	3 years
Computers, Office Furniture and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	5 years

[1] The Condensed Consolidated Balance Sheet as of March 31, 2016 has been derived from the audited Consolidated Financial Statements at that date but does not include all disclosures required by generally accepted accounting principles for complete financial statements.