v3.7.0.1

Restructuring Charges - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Apr. 30, 2017 | Jan. 31, 2017 | Oct. 31, 2016 | Jul. 31, 2016 | Apr. 30, 2016 | Jan. 31, 2016 | Oct. 31, 2015 | Jul. 31, 2015 | Apr. 30, 2017 | Apr. 30, 2016 | Apr. 30, 2015
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring charges | $ 1,108 | $ 0 | $ 767 | $ 327 | $ 1,575 | $ 0 | $ 0 | $ 0 | $ 2,202 | $ 1,575 | $ 0
Employee Severance [Member] |  |  |  |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | 1,567 | 1,029 |
Other Restructuring [Member] |  |  |  |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | 635 | 546 |
2016 Plan [Member] |  |  |  |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | 1,100 | $ 1,600 |
Restructuring and Related Cost, Cost Incurred to Date | $ 2,700 |  |  |  |  |  |  |  | 2,700 |  |
2017 Plan [Member] |  |  |  |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | $ 1,100 |  |

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- Definition Amount of costs incurred to date for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + Details
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- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.P.3) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + 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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