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Stock Plans (Detail Textuals) - USD ($) | Aug. 31, 2019 | May 31, 2019
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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

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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Details
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