Share-Based Compensation, Performance-Based Market Stock Units (Details) - shares		12 Months Ended
		Jul. 28, 2017	Jul. 29, 2016	Jul. 31, 2015
MSU Grants [Member]
Fair Value Assumptions and Methodology [Abstract]
Dividend yield	[1]		0.00%	0.00%
Expected volatility, minimum			23.00%
Expected volatility				21.00%
Expected volatility, maximum			24.00%
Risk-free interest rate, minimum			0.90%
Risk-free interest rate				1.00%
Risk-free interest rate, maximum			1.00%
2015 MSU Grants [Member]
Fair Value Assumptions and Methodology [Abstract]
Number of shares accrued (in shares)		39,467
2016 MSU Grants [Member]
Fair Value Assumptions and Methodology [Abstract]
Number of shares accrued (in shares)		14,565
Omnibus Plan 2010 [Member] | MSU Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years
Measurement period for average stock prices in consecutive calendar days		60 days
Measurement period for average stock prices prior to first business day of performance period		30 days
Measurement period for average stock prices after first business day of performance period		30 days
Omnibus Plan 2010 [Member] | MSU Grants [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares of target award that may be awarded		150.00%

[1] Dividends accrue on the 2015 and 2016 MSU Grants. Dividends will be forfeited for any MSU Grants that do not vest. No MSU Grants were awarded in 2017.