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Business Acquisitions (Schedule of Unaudited Proforma Combined Financial Information) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jan. 31, 2013 | Jan. 31, 2012 | Jan. 31, 2013 | Jan. 31, 2012
Business Acquisition [Line Items] |  |  |  |
Revenue | $ 116,291 | $ 119,456 | $ 366,089 | $ 386,578
Operating income | 40 | 4,753 | 10,748 | 27,306
Net loss attributable to common stockholders | $ (11,442) | $ (24,795) | $ (41,042) | $ (28,951)
Basic and diluted loss per common share attributable to common stockholders | $ (0.29) | $ (0.92) | $ (1.27) | $ (1.08)
Basic and diluted weighted average shares outstanding | 39,230 | 26,822 | 32,365 | 26,715

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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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