Consolidated Statements of Stockholders' Equity (Parenthetical) (Unaudited)	3 Months Ended
Aug. 31, 2019 shares
Repurchase of shares of common stock	208,312
Common Stock [Member]
Repurchase of shares of common stock	208,312

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Name:	us-gaap_StockRepurchasedDuringPeriodShares
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration