Revenue Recognition - Additional Information (Detail)	3 Months Ended
Aug. 31, 2018
Minimum
Revenue Recognition [Line Items]
Period allowed for payment of dues to customers	30 days
Maximum
Revenue Recognition [Line Items]
Period allowed for payment of dues to customers	60 days
Maximum \| Accounting Standards Update 2014-09
Revenue Recognition [Line Items]
Duraton to satisfy performance obligation for contracts	1 year

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

Name:	us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant