v2.4.0.8

Computations of Loss per Share Applicable to Common Stockholders (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified | 3 Months Ended | 12 Months Ended
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Apr. 30, 2014 | Jan. 31, 2014 | Oct. 31, 2013 | Jul. 31, 2013 | Apr. 30, 2013 | Jan. 31, 2013 | Oct. 31, 2012 | Jul. 31, 2012 | Apr. 30, 2014 | Apr. 30, 2013 | Apr. 30, 2012
Schedule Of Computation Of Basic And Diluted Earnings Per Common Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss from continuing operations | $ (12,233) | $ (8,393) | $ (14,574) | $ (17,646) | $ (23,020) | $ (9,807) | $ (9,020) | $ (5,656) | $ (52,846) |  | $ (47,503) |  | $ (24,329) |
Less accretion of redeemable convertible preferred stock |  |  |  |  |  |  |  |  |  |  |  |  | (38) |
Net loss applicable to common stockholders |  |  |  |  |  |  |  |  | $ (52,846) |  | $ (47,503) |  | $ (24,367) |
Net loss per share applicable to common stockholders, basic and diluted |  |  |  |  |  |  |  |  | $ (0.70) |  | $ (0.69) |  | $ (0.92) |
Weighted average number of shares outstanding, basic and diluted |  |  |  |  |  |  |  |  | 75,564 |  | 69,336 |  | 26,403 |
Outstanding stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities |  |  |  |  |  |  |  |  | 2,149 | [1] | 5,718 | [1] | 6,241 | [1]
Redeemable Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities |  |  |  |  |  |  |  |  |  |  |  |  | 22,714 | [1]
Restricted Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potentially dilutive securities |  |  |  |  |  |  |  |  | 293 | [1] | 67 | [1] | 1 | [1]
[1] | The impact of potentially dilutive securities on earnings per share is anti-dilutive in a period of net loss.

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + 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 (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Diluted Earnings Per Share -URI http://asc.fasb.org/extlink&oid=6510752 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 + Details
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- Definition Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4613673-111683 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.13) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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- Definition The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1377-109256 + Details
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