v2.4.0.8

Accrued Expenses and Other Current Liabilities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | Feb. 28, 2012 | Oct. 31, 2009 | Apr. 30, 2014 Accrued Liabilities | Apr. 30, 2013 Accrued Liabilities | Apr. 30, 2014 Other Long Term Liabilities | Apr. 30, 2013 Other Long Term Liabilities
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Accrued Expenses and Other Current Liabilities [Line Items] |  |  |  |  |  |
Leasehold improvement incentives received | $ 0.6 | $ 2.9 | $ 1.2 | $ 0.7 | $ 1.2 | $ 2.3

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- Definition This item represents an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 + Details
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