Stock Plans (Detail Textuals) - USD ($)	Aug. 31, 2019	May 31, 2019
New Stock Repurchase Program \| Common Stock
Equity Class Of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 1,000,000.0	$ 8,000,000.0

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.

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