v3.7.0.1

Income Taxes - Aggregate Changes in Balance of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Apr. 30, 2017 | Apr. 30, 2016 | Apr. 30, 2015
Income Tax Disclosure [Abstract] |  |  |
Beginning unrecognized tax benefits | $ 4,193 | $ 3,619 | $ 2,157
Tax positions taken in prior periods: |  |  |
Gross increases | 0 | 88 | 883
Gross decreases | (199) | (42) | 0
Tax positions taken in current period: |  |  |
Gross increases | 595 | 528 | 579
Lapse of statute of limitations | (68) | 0 | 0
Ending unrecognized tax benefits | $ 4,521 | $ 4,193 | $ 3,619

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- Definition Tax Positions Taken In Prior Periods [Abstract] + References No definition available. + Details
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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319 + Details
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