CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]
Balance (in shares) at Jul. 28, 2018		10,575	4,304			496
Balance at Jul. 28, 2018	$ 303,145	$ 61,678	$ 699	$ 258,104	$ (8,185)	$ (9,151)
Net income	18,810			18,810
Other comprehensive income, net of tax	608				608
Dividends	(9,658)			(9,658)
Exercise of stock options (in shares)						(36)
Exercise of stock options	1,008	$ 337				$ 671
Treasury stock purchases (in shares)						28
Restricted shares forfeited	(729)					$ (729)
Restricted shares forfeited (in shares)		(9)
Restricted shares forfeited	(127)	$ (127)
Share-based compensation expense (in shares)		20
Share-based compensation expense	2,514	$ 2,514
Conversion of Class B shares to Class A shares (in shares)		10	(10)
Conversion of Class B shares to Class A shares	0	$ 2	$ (2)
Balance (in shares) at Apr. 27, 2019		10,596	4,294			488
Balance at Apr. 27, 2019	315,571	$ 64,404	$ 697	267,256	(7,577)	$ (9,209)
Balance (in shares) at Jan. 26, 2019		10,574	4,304			524
Balance at Jan. 26, 2019	311,540	$ 63,194	$ 699	265,508	(7,981)	$ (9,880)
Net income	4,970			4,970
Other comprehensive income, net of tax	404				404
Dividends	(3,222)			(3,222)
Exercise of stock options (in shares)						(36)
Exercise of stock options	1,008	$ 337				$ 671
Share-based compensation expense (in shares)		12
Share-based compensation expense	871	$ 871
Conversion of Class B shares to Class A shares (in shares)		10	(10)
Conversion of Class B shares to Class A shares	0	$ 2	$ (2)
Balance (in shares) at Apr. 27, 2019		10,596	4,294			488
Balance at Apr. 27, 2019	315,571	$ 64,404	$ 697	267,256	(7,577)	$ (9,209)
Balance (in shares) at Jul. 27, 2019		10,593	4,294			502
Balance at Jul. 27, 2019	318,672	$ 65,114	$ 697	270,753	(8,342)	$ (9,550)
Net income	15,724			15,724
Other comprehensive income, net of tax	876				876
Dividends	(9,697)			(9,697)
Treasury stock purchases (in shares)						224
Restricted shares forfeited	(4,389)					$ (4,389)
Restricted shares forfeited (in shares)		(10)
Restricted shares forfeited	(199)	$ (199)
Share-based compensation expense (in shares)		387
Share-based compensation expense	2,507	$ 2,507
Balance (in shares) at Apr. 25, 2020		10,970	4,294			726
Balance at Apr. 25, 2020	327,008	$ 67,422	$ 697	280,294	(7,466)	$ (13,939)
Balance (in shares) at Jan. 25, 2020		10,586	4,294			513
Balance at Jan. 25, 2020	321,982	$ 66,655	$ 697	272,401	(7,972)	$ (9,799)
Net income	11,152			11,152
Other comprehensive income, net of tax	506				506
Dividends	(3,259)			(3,259)
Treasury stock purchases (in shares)						213
Restricted shares forfeited	(4,140)					$ (4,140)
Restricted shares forfeited (in shares)		(1)
Restricted shares forfeited	(19)	$ (19)
Share-based compensation expense (in shares)		385
Share-based compensation expense	786	$ 786
Balance (in shares) at Apr. 25, 2020		10,970	4,294			726
Balance at Apr. 25, 2020	$ 327,008	$ 67,422	$ 697	$ 280,294	$ (7,466)	$ (13,939)