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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
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Jan. 31, 2014 | Jan. 31, 2013 | Jan. 31, 2014 | Jan. 31, 2013
Business Combinations [Abstract] |  |  |  |
Revenue | $ 118,210 | $ 116,385 | $ 382,786 | $ 366,889
Operating (loss) income | (1,215) | 584 | 18,671 | 12,227
Net loss attributable to common stockholders | $ (10,721) | $ (11,274) | $ (10,965) | $ (40,537)
Basic and diluted loss per common share attributable to common stockholders | $ (0.27) | $ (0.29) | $ (0.28) | $ (1.25)
Basic and diluted weighted average shares outstanding | 39,882 | 39,230 | 39,789 | 32,365

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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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