Calculation of Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Sep. 01, 2018	Sep. 02, 2017
Numerator for Basic and Diluted Earnings Per Share:
Net income (loss)	$ 431	$ (112)
Undistributed losses, basic	(333)	(870)
Undistributed losses, Diluted	(333)	(870)
Basic
Numerator for Basic and Diluted Earnings Per Share:
Net income (loss)	431	(112)
Diluted
Numerator for Basic and Diluted Earnings Per Share:
Net income (loss)	$ 431	$ (112)
Denominator for basic and diluted Earnings Per Share:
Effect of dilutive securities dilutive stock options	153
Weighted Average Number of Shares Outstanding, Diluted	13,114	12,849
Common Class B
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, basic	$ (50)	$ (132)
Undistributed losses, Diluted	$ (50)	$ (132)
Denominator for basic and diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	2,132	2,137
Weighted Average Number of Shares Outstanding, Diluted	2,132	2,137
Earnings Per Share, Basic and Diluted [Abstract]
Earnings Per Share, Basic	$ 0.03	$ (0.01)
Earnings Per Share, Diluted	$ 0.03	$ (0.01)
Common Class B \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 116	$ 115
Common Class B \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	116	115
Common Stock
Numerator for Basic and Diluted Earnings Per Share:
Undistributed losses, basic	(283)	(738)
Undistributed losses, Diluted	$ (283)	$ (738)
Denominator for basic and diluted Earnings Per Share:
Weighted Average Number of Shares Outstanding, Basic	10,829	10,712
Weighted Average Number of Shares Outstanding, Diluted	10,982	10,712
Earnings Per Share, Basic and Diluted [Abstract]
Earnings Per Share, Basic	$ 0.03	$ (0.01)
Earnings Per Share, Diluted	$ 0.03	$ (0.01)
Common Stock \| Basic
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 648	$ 643
Common Stock \| Diluted
Numerator for Basic and Diluted Earnings Per Share:
Less dividends	$ 648	$ 643

Denominator for Basic and Diluted Earnings Per Share:

No definition available.

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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