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Summary Of Significant Accounting Policies (Tables) | 12 Months Ended
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Mar. 31, 2013
Summary Of Significant Accounting Policies [Abstract] |
Estimated Useful Life Of Property, Plant And Equipment |
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 |
|  | Year ended March 31,
|  | 2013 |  |  | 2012 |  |  | 2011
Numerator: |  |  |  |  |  |  |  |
Net loss | $ | (66,131) |  | $ | (136,827) |  | $ | (186,284)
Denominator: |  |  |  |  |  |  |  |
Weighted-average shares of common stock outstanding |  | 53,537 |  |  | 51,144 |  |  | 47,750
Weighted-average shares subject to repurchase |  | (467) |  |  | (302) |  |  | (647)
Shares used in per-share calculation ― basic |  | 53,070 |  |  | 50,842 |  |  | 47,103
Dilutive effect of employee equity incentive plans |  | - |  |  | - |  |  | -
Shares used in per-share calculation ― diluted |  | 53,070 |  |  | 50,842 |  |  | 47,103
Net loss per share ― basic | $ | (1.25) |  | $ | (2.69) |  | $ | (3.95)
Net loss per share ― diluted | $ | (1.25) |  | $ | (2.69) |  | $ | (3.95)

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- Definition Tabular disclosure of the numerators and the denominators of the basic and diluted per-share (or per-unit) computations for income from continuing operations, including the effect that has been given to preferred dividends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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