v3.8.0.1

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Oct. 31, 2017 Customer | Oct. 31, 2016 Customer | Oct. 31, 2017 Customer | Oct. 31, 2016 Customer | Apr. 30, 2017 USD ($) Customer
Accounting Policies [Abstract] |  |  |  |  |
Number of clients that accounted for more than 10% of account receivables | Customer | 0 |  | 0 |  | 0
Number of clients that accounted for more than 10% of revenue | Customer | 0 | 0 | 0 | 0 |
Adjustments for New Accounting Pronouncement [Member] |  |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |  |
Deferred Tax Assets, Other |  |  |  |  | $ 12,700
Deferred Tax Assets, Valuation Allowance |  |  |  |  | 12,700
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | $ 326
Minimum [Member] | Software as a Service (“SaaS”) |  |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |  |
Service agreement period |  |  | 1 year |  |
Maximum [Member] | Software as a Service (“SaaS”) |  |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |  |
Service agreement period |  |  | 3 years |  |

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- Definition Number of Customers With Greater Than Ten Percent Accounts Receivable Balance + References No definition available. + Details
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- Definition Number of Customers With Greater Than Ten Percent Revenue + References No definition available. + Details
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=68052875&loc=d3e28680-109314 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319 + Details
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