CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Jul. 27, 2019	Jul. 28, 2018
Preferred stock shares authorized (in shares)	10,000,000	10,000,000
Preferred stock shares issued (in shares)	0	0
Class A Common Stock
Common stock shares authorized (in shares)	20,000,000	20,000,000
Common stock shares issued (in shares)	10,593,000	10,575,000
Treasury stock shares (in shares)	502,000	496,000
Class B Common Stock
Common stock shares authorized (in shares)	20,000,000	20,000,000
Common stock shares issued (in shares)	4,294,000	4,304,000
Common stock shares outstanding (in shares)	4,294,000	4,304,000