Restructuring Charges, Net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 78	$ 34,600	$ 33,013
Restructuring liability included in other long-term liabilities	1,000	4,600
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net		15,963	32,100
Facilities
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 78	$ 18,637	$ 900

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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

Name:	us-gaap_RestructuringReserveNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant