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Business Acquisitions - Schedule of Unaudited Proforma Combined Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified | 12 Months Ended
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Apr. 30, 2013 | Apr. 30, 2012 | Apr. 30, 2011
Business Acquisition [Line Items] |  |  |
Revenue | $ 465,083 | $ 487,707 |
Operating income (loss) | 13,118 | (9,670) |
Net loss attributable to common stockholders | $ (54,440) | $ (78,230) |
Basic and diluted loss per common share attributable to common stockholders | $ (1.60) | $ (2.92) |
Basic and diluted weighted average shares outstanding | 34,015 | 26,749 | 26,105

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- Definition The pro forma basic and diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References No definition available. + Details
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- Definition The pro forma operating income for the period as if the business combination or combinations had been completed at the beginning of the period. + References No definition available. + Details
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463 + Details
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463 + Details
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