Share-Based Compensation, Stock Options (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Jul. 28, 2017	Jul. 29, 2016	Jul. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Yearly exercisable cumulative rate		33.00%
Number of years to expiration date from grant date		10 years
Fixed options, shares [Roll Forward]
Outstanding, beginning of period (in shares)		12,683
Granted (in shares)		0	0	0
Exercised (in shares)		(8,683)
Forfeited (in shares)		0
Canceled (in shares)		0
Outstanding, end of period (in shares)		4,000	12,683
Exercisable (in shares)		4,000
Fixed options, weighted-average price [Roll Forward]
Outstanding, beginning of period (in dollars per share)		$ 32.71
Granted (in dollars per share)		0
Exercised (in dollars per share)		32.64
Forfeited (in dollars per share)		0
Canceled (in dollars per share)		0
Outstanding, end of period (in dollars per share)		32.86	$ 32.71
Exercisable (in dollars per share)		$ 32.86
Fixed options, weighted-average remaining contractual term [Abstract]
Outstanding		3 months 29 days
Exercisable		3 months 29 days
Fixed options, aggregate intrinsic value [Abstract]
Outstanding		$ 490
Exercisable		490
Total intrinsic values of options exercised	[1]	$ 1,070	$ 917	$ 4,652

[1] The intrinsic value for stock options is defined as the difference between the current market value and the grant price.