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Stockholders' (Deficit) Equity - Summary of Grant Activity for Other Stock Awards (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified | 12 Months Ended
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Apr. 30, 2014 | Apr. 30, 2013 | Apr. 30, 2012
Schedule Of Stock Option Activity [Line Items] |  |  |
Stock Options, Granted | 542 | 735 | 611
Stock Options, Weighted Average Grant Date Fair Value | $ 4.28 |  |
Stock Options, Unissued | 454 | 431 | 62
Restricted Stock Units [Member] |  |  |
Schedule Of Stock Option Activity [Line Items] |  |  |
Stock Options, Granted | 482 | 340 | 305
Stock Options, Weighted Average Grant Date Fair Value | $ 4.09 | $ 5.15 | $ 6.12
Stock Options, Unissued | 454 | 176 | 62
Performance Stock Units [Member] |  |  |
Schedule Of Stock Option Activity [Line Items] |  |  |
Stock Options, Granted |  | 316 | 255
Stock Options, Weighted Average Grant Date Fair Value |  | $ 5.17 | $ 6.06
Stock Options, Unissued |  | 255 |
Restricted Stock Awards [Member] |  |  |
Schedule Of Stock Option Activity [Line Items] |  |  |
Stock Options, Granted | 60 | 79 | 51
Stock Options, Weighted Average Grant Date Fair Value | $ 5.81 | $ 4.45 | $ 5.83
Stock Options, Unissued |  |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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