Calculation of Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2019	Dec. 01, 2018	Nov. 30, 2019	Dec. 01, 2018
Numerator for Basic and Diluted Earnings Per Share:
Net (loss) income	$ (622)	$ (304)	$ (465)	$ 127
Undistributed losses, Basic	(1,397)	(1,074)	(2,015)	(1,407)
Undistributed losses, Diluted	$ (1,397)	$ (1,074)	$ (2,015)	$ (1,407)
Denominator for Basic and Diluted Earnings Per Share:
Effect of dilutive securities dilutive stock options				163
Weighted Average Number of Shares Outstanding, Diluted	13,135	13,049	13,111	13,167
Basic
Numerator for Basic and Diluted Earnings Per Share:
Net (loss) income	$ (622)	$ (304)	$ (465)	$ 127
Diluted
Numerator for Basic and Diluted Earnings Per Share:
Net (loss) income	(622)	(304)	(465)	127
Common Class B
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(204)	(158)	(295)	(209)
Undistributed losses, Diluted	$ (204)	$ (158)	$ (295)	$ (207)
Denominator for Basic and Diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	2,097	2,097	2,097	2,114
Weighted Average Number of Shares Outstanding, Diluted	2,097	2,097	2,097	2,114
Net (loss) income per share:
Earnings Per Share, Basic	$ (0.04)	$ (0.02)	$ (0.03)	$ 0.01
Earnings Per Share, Diluted	$ (0.04)	$ (0.02)	$ (0.03)	$ 0.01
Common Class B \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 113	$ 112	$ 226	$ 228
Common Class B \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	113	112	226	228
Common Stock
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(1,193)	(916)	(1,720)	(1,198)
Undistributed losses, Diluted	$ (1,193)	$ (916)	$ (1,720)	$ (1,200)
Denominator for Basic and Diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	11,038	10,952	11,014	10,890
Weighted Average Number of Shares Outstanding, Diluted	11,038	10,952	11,014	11,053
Net (loss) income per share:
Earnings Per Share, Basic	$ (0.05)	$ (0.02)	$ (0.04)	$ 0.01
Earnings Per Share, Diluted	$ (0.05)	$ (0.02)	$ (0.04)	$ 0.01
Common Stock \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 658	$ 1,324	$ 1,306
Common Stock \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 658	$ 1,324	$ 1,306

Denominator for Basic and Diluted Earnings Per Share:

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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