Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Nov. 02, 2019	Jul. 31, 2019
Assets
Property, buildings and equipment, accumulated depreciation	$ 17,193	$ 17,066
Shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock, shares issued (in shares)	0	0
Class A [Member]
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	6,000,000	6,000,000
Common stock, shares issued (in shares)	3,202,047	3,192,990
Treasury stock (in shares)	63,724	64,823
Class B [Member]
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, shares issued (in shares)	1,191,678	1,200,735