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Business Acquisitions - Schedule of Unaudited Proforma Combined Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified | 3 Months Ended
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Jul. 31, 2013 | Jul. 31, 2012
Business Combinations [Abstract] |  |
Revenue | $ 128,558 | $ 121,851
Operating income | 9,737 | 6,105
Net loss attributable to common stockholders | $ (191) | $ (8,506)
Basic and diluted loss per common share attributable to common stockholders | $ 0.00 | $ (0.32)
Basic and diluted weighted average shares outstanding | 39,662 | 26,992

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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=25497992&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=25497992&loc=d3e1392-128463 + Details
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- Definition Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS). + References No definition available. + Details
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