v3.7.0.1

Stockholders' Equity - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands | 12 Months Ended
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Apr. 30, 2017 | Apr. 30, 2016 | Apr. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | $ 16,282 | $ 15,086 | $ 12,201
Capitalized stock-based compensation | 495 | 488 | 601
Stock-based compensation | 16,777 | 15,574 | 12,802
Cost of Sales [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | 1,734 | 2,167 | 1,517
Selling and Marketing Expense [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | 2,996 | 2,956 | 3,923
Research and Development Expense [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | 3,770 | 2,996 | 1,960
General and Administrative Expense [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | 7,782 | 6,967 | 4,677
Loss From Discontinued Operations, Net Of Tax [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Stock-based expense | $ 0 | $ 0 | $ 124

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- Definition This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation". + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66904339&loc=d3e4534-113899 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65896087&loc=d3e11149-113907 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=65896087&loc=d3e11178-113907 + Details
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- Definition Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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. + References No definition available. + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + 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 (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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