v3.5.0.1

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands | 12 Months Ended
--- | ---
Apr. 30, 2016 USD ($) Customer | Apr. 30, 2015 USD ($) Customer | Apr. 30, 2014 USD ($) Customer
Accounting Policies [Abstract] |  |  |
Foreign Currency Transaction Gain (Loss), before Tax | $ (400) | $ (1,000) | $ 400
Other than Temporary Impairment Losses, Investments | 0 | 0 | $ 0
Allowance for doubtful accounts | $ 2,362 | $ 3,992 |
Number of clients that accounted for more than 10% of account receivables | Customer | 0 | 0 |
Number of clients that accounted for more than 10% of revenue | Customer | 0 | 0 | 0
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |
Stock-based expense | $ 14,761 | $ 12,201 | $ 13,827
Software as a Service (“SaaS”) |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |
Service agreement period | 1 year |  |

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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 A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524 + Details
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- Definition Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894 + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560 + Details
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