Number of Customers With Greater Than Ten Percent Accounts Receivable Balance

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Number of Customers With Greater Than Ten Percent Revenue

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Revenue Recognition, Service Agreement, Period

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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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

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-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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 25
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=68052875&loc=d3e28680-109314

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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