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)

v2.4.0.8

Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Restricted Cash
Additional security maintained with Wells Fargo for line of credit				$ 1,300,000
Restricted cash released by Wells Fargo			(1,250,000)
Long-Lived Assets
Impairment	0
Revenue
Term for advance payment from shipment of sales	90 days
Research and Development ("R&D")
Total offsets to R&D expenses	1,400,000	1,700,000	800,000
Risk Concentrations
Aggregate balances that exceed insurance coverage	27,600,000
Accounts receivable allowances	242,000	276,000	2,256,000
Net Loss Per Common Share
Options outstanding (in shares)	12,900,000	11,800,000	10,000,000
Outstanding restricted stock units (in shares)	2,100,000	1,500,000	1,100,000
Number of warrants excluded from diluted net loss per common share computations	0	26,500,000	26,500,000
Revenue \| Customer concentrations \| E-Finity
Risk Concentrations
Concentration percentage	19.00%
Revenue \| Customer concentrations \| Horizon
Risk Concentrations
Concentration percentage	12.00%	27.00%	19.00%
Revenue \| Customer concentrations \| BPC
Risk Concentrations
Concentration percentage	17.00%	11.00%	26.00%
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%	35.00%
Net accounts receivable \| Credit concentration \| Regatta
Risk Concentrations
Concentration percentage		11.00%
Net accounts receivable \| Credit concentration \| EMI
Risk Concentrations
Concentration percentage	18.00%
DOE
Risk Concentrations
Other receivables under grants awarded	$ 0	$ 300,000
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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