Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Summary of Significant Accounting Policies (Details)

v2.4.1.9

Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended			9 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2014	Sep. 30, 2013
Inventories
Increase in inventory charges	$ 1,000,000
Long-Lived Assets
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Revenue
Term for advance payment from shipment of sales	90 days
Research and Development ("R&D")
Total offsets to R&D expenses	500,000	1,400,000	1,700,000
Risk Concentrations
Aggregate balances that exceed insurance coverage	32,000,000us-gaap_CashUninsuredAmount
Bad debt expense	10,138,000us-gaap_ProvisionForDoubtfulAccounts	242,000us-gaap_ProvisionForDoubtfulAccounts	276,000us-gaap_ProvisionForDoubtfulAccounts
Net Loss Per Common Share
Options outstanding (in shares)	13,200,000	12,900,000	11,800,000
Outstanding restricted stock units (in shares)	1,900,000	2,100,000	1,500,000
Number of warrants excluded from diluted net loss per common share computations	0	0	26,500,000
Revenue \| Customer concentrations \| E-Finity
Risk Concentrations
Concentration percentage		19.00%
Revenue \| Customer concentrations \| Horizon
Risk Concentrations
Concentration percentage	17.00%	12.00%	27.00%
Revenue \| Customer concentrations \| BPC
Risk Concentrations
Concentration percentage	11.00%	17.00%	11.00%
Accounts receivable allowance	7,100,000
Net accounts receivable \| Credit concentration \| E-Finity
Risk Concentrations
Concentration percentage		16.00%
Net accounts receivable \| Credit concentration \| BPC
Risk Concentrations
Concentration percentage		26.00%		17.00%
Accounts receivable allowance					$ 2,600,000
Net accounts receivable \| Credit concentration \| EMI
Risk Concentrations
Concentration percentage		18.00%
Minimum
Depreciation and Amortization
Estimated Useful Life	2 years
Maximum
Depreciation and Amortization
Estimated Useful Life	10 years
Warranty
Warranty period	18 months

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