Certain Financial Statement Information - Property and Equipment (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2015	Mar. 31, 2015
Schedule of Property and equipment
Machinery and equipment	$ 37,795	$ 37,286
Leasehold improvements	7,533	9,909
Computers, office furniture and equipment	33,904	32,902
Property and equipment, gross	79,232	80,097
Less: accumulated depreciation	(64,817)	(63,348)
Property and equipment, net	$ 14,415	$ 16,749	[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, 2015 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.