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. 29, 2017		10,562	4,304			477
Balance at Jul. 29, 2017	$ 286,820	$ 57,852	$ 699	$ 244,308	$ (7,406)	$ (8,633)
Net income	19,070			19,070
Other comprehensive income, net of tax	285				285
Dividends	(9,656)			(9,656)
Treasury stock purchases (in shares)						27
Treasury stock purchases	(632)					$ (632)
Restricted shares forfeited (in shares)		(6)
Restricted shares forfeited	(49)	$ (49)
Share-based compensation expense (in shares)		20
Share-based compensation expense	2,564	$ 2,564
Balance (in shares) at Apr. 28, 2018		10,576	4,304			504
Balance at Apr. 28, 2018	298,402	$ 60,367	$ 699	253,722	(7,121)	$ (9,265)
Balance (in shares) at Jan. 27, 2018		10,569	4,304			504
Balance at Jan. 27, 2018	294,185	$ 59,573	$ 699	250,398	(7,220)	$ (9,265)
Net income	6,542			6,542
Other comprehensive income, net of tax	99				99
Dividends	(3,218)			(3,218)
Restricted shares forfeited (in shares)		(5)
Restricted shares forfeited	(43)	$ (43)
Share-based compensation expense (in shares)		12
Share-based compensation expense	837	$ 837
Balance (in shares) at Apr. 28, 2018		10,576	4,304			504
Balance at Apr. 28, 2018	298,402	$ 60,367	$ 699	253,722	(7,121)	$ (9,265)
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
Treasury stock purchases	(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		$ 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		$ 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)