Calculation of Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Feb. 29, 2020	Mar. 02, 2019	Feb. 29, 2020	Mar. 02, 2019
Numerator for Basic and Diluted Earnings Per Share:
Net loss	$ (93)	$ (1,078)	$ (558)	$ (951)
Undistributed losses, Basic	(869)	(1,849)	(2,884)	(3,256)
Undistributed losses, Diluted	$ (869)	$ (1,849)	$ (2,884)	$ (3,256)
Denominator for Basic and Diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Diluted	13,135	13,050	13,119	13,019
Basic
Numerator for Basic and Diluted Earnings Per Share:
Net loss	$ (93)	$ (1,078)
Diluted
Numerator for Basic and Diluted Earnings Per Share:
Net loss	(93)	(1,078)
Common Class B
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(127)	(272)	$ (422)	$ (482)
Undistributed losses, Diluted	$ (127)	$ (272)	$ (422)	$ (482)
Denominator for Basic and Diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	2,097	2,097	2,097	2,108
Weighted Average Number of Shares Outstanding, Diluted	2,097	2,097	2,097	2,108
Net loss per share:
Earnings Per Share, Basic	$ (0.01)	$ (0.08)	$ (0.04)	$ (0.07)
Earnings Per Share, Diluted	$ (0.01)	$ (0.08)	$ (0.04)	$ (0.07)
Common Class B \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 114	$ 114	$ 340	$ 342
Common Class B \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	114	114	340	342
Common Stock
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, Basic	(742)	(1,577)	(2,462)	(2,774)
Undistributed losses, Diluted	$ (742)	$ (1,577)	$ (2,462)	$ (2,774)
Denominator for Basic and Diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	11,038	10,953	11,022	10,911
Weighted Average Number of Shares Outstanding, Diluted	11,038	10,953	11,022	10,911
Net loss per share:
Earnings Per Share, Basic	$ (0.01)	$ (0.08)	$ (0.04)	$ (0.07)
Earnings Per Share, Diluted	$ (0.01)	$ (0.08)	$ (0.04)	$ (0.07)
Common Stock \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 657	$ 1,986	$ 1,963
Common Stock \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 662	$ 657	$ 1,986	$ 1,963

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

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