v3.7.0.1

Employee Benefit Plan - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Apr. 30, 2017 | Apr. 30, 2016 | Apr. 30, 2015
Postemployment Benefits [Abstract] |  |  |
Defined Contribution Plan, Cost Recognized | $ 0.8 | $ 0.8 | $ 0.7

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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
Name: | us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- References No definition available. + Details
Name: | us-gaap_PostemploymentBenefitsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration