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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Mar. 31, 2015
Accounting Policies [Abstract] |
Estimated Useful Life of Property, Plant and Equipment | Property, plant and equipment are carried at cost less accumulated depreciation and amortization. The Company accounts for depreciation and amortization using the straight-line method to allocate the cost of property, plant and equipment over their estimated useful lives as follows:
Asset Classification |  | Estimated Useful Life in Years
Building |  | 40
Process upgrades to the building |  | 10-40
Machinery and equipment |  | 3-10
Furniture and fixtures |  | 3-5
Leasehold improvements |  | Shorter of the estimated useful life or the remaining lease term
Reconciliation of Numerators and Denominators of EPS Calculation | The following table reconciles the numerators and denominators of the EPS calculation for the years ended March 31, 2015, 2014, and 2013 (in thousands except per share amounts):
| Year ended March 31, |
| 2015 |  |  | 2014 |  |  | 2013 |
Numerator: |  |  |  |  |  |  |  |  |  |  |
Net loss | $ | (48,656 | ) |  | $ | (56,258 | ) |  | $ | (66,131 | )
Denominator: |  |  |  |  |  |  |  |  |  |  |
Weighted-average shares of common stock outstanding |  | 8,559 |  |  |  | 6,411 |  |  |  | 5,354 |
Weighted-average shares subject to repurchase |  | (82 | ) |  |  | (149 | ) |  |  | (47 | )
Shares used in per-share calculation ― basic |  | 8,477 |  |  |  | 6,262 |  |  |  | 5,307 |
Shares used in per-share calculation ― diluted |  | 8,477 |  |  |  | 6,262 |  |  |  | 5,307 |
Net loss per share ― basic | $ | (5.74 | ) |  | $ | (8.98 | ) |  | $ | (12.46 | )
Net loss per share ― diluted | $ | (5.74 | ) |  | $ | (8.98 | ) |  | $ | (12.46 | )

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- Definition Schedule of estimated useful life of property, plant and equipment. + References No definition available. + Details
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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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