Guarantees - Additional Information (Detail) - Stand-by Letters of Credit	3 Months Ended
Aug. 31, 2020 USD ($)
Guarantee Obligations [Line Items]
Letter of credit amount outstanding	$ 15,050,000
Drawn amount of letter of credit outstanding	$ 0

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.

No definition available.

Name:	us-gaap_GuaranteeObligationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration