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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 | 6 Months Ended
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Oct. 31, 2013 | Oct. 31, 2012 | Oct. 31, 2013 | Oct. 31, 2012
Business Combinations [Abstract] |  |  |  |
Revenue | $ 132,857 | $ 124,091 | $ 263,134 | $ 249,062
Operating income | 9,508 | 4,897 | 19,421 | 11,177
Net loss attributable to common stockholders | $ (312) | $ (21,016) | $ (426) | $ (29,442)
Basic and diluted loss per common share attributable to common stockholders | $ (0.01) | $ (0.68) | $ (0.01) | $ (1.02)
Basic and diluted weighted average shares outstanding | 39,821 | 30,872 | 39,742 | 28,932

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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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