Calculation of Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Aug. 31, 2019	Sep. 01, 2018
Numerator for Basic and Diluted Earnings Per Share:
Net income	$ 157	$ 431
Undistributed losses, Basic	(618)	(333)
Undistributed losses, Diluted	$ (618)	$ (333)
Denominator for basic and diluted Earnings Per Share:
Effect of dilutive securities dilutive stock options		153
Weighted Average Number of Shares Outstanding, Diluted	13,087	13,114
Basic
Numerator for Basic and Diluted Earnings Per Share:
Net income	$ 157	$ 431
Diluted
Numerator for Basic and Diluted Earnings Per Share:
Net income	157	431
Common Class B
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(91)	(50)
Undistributed losses, Diluted	$ (91)	$ (50)
Denominator for basic and diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	2,097	2,132
Weighted Average Number of Shares Outstanding, Diluted	2,097	2,132
Net income per share:
Earnings Per Share, Basic	$ 0.01	$ 0.03
Earnings Per Share, Diluted	$ 0.01	$ 0.03
Common Class B | Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 113	$ 116
Common Class B | Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	113	116
Common Stock
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(527)	(283)
Undistributed losses, Diluted	$ (527)	$ (283)
Denominator for basic and diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	10,990	10,829
Weighted Average Number of Shares Outstanding, Diluted	10,990	10,982
Net income per share:
Earnings Per Share, Basic	$ 0.01	$ 0.03
Earnings Per Share, Diluted	$ 0.01	$ 0.03
Common Stock | Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 648
Common Stock | Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 648