Accounting Policies (Details) (USD $)					12 Months Ended
	Jul. 27, 2013	Jul. 28, 2012	Jul. 27, 2013 Long Term Incentive Plan, 2012	Nov. 20, 2012 Long Term Incentive Plan, 2012	Jul. 27, 2013 Stock Options	Jul. 27, 2013 Restricted Share Units (RSUs)	Jul. 27, 2013 Performance Restricted Share Units	Jul. 27, 2013 Common Stock Restricted Share Units (RSUs)	Jul. 27, 2013 Senior Subordinated Notes 7.125% Senior Subordinated Notes Due 2021	Jul. 28, 2012 Senior Subordinated Notes 7.125% Senior Subordinated Notes Due 2021	Jul. 30, 2011 Senior Subordinated Notes 7.125% Senior Subordinated Notes Due 2021
Debt Instrument [Line Items]
Restricted cash		$ 3,700,000
Capitalized computer software gross cost	18,300,000	11,600,000
Capitalized computer software net book value	11,600,000	7,400,000
Accrued Insurance	56,319,000	48,809,000
Accrued insurance incurred	26,000,000	22,300,000
Accrued insurance claims	$ 29,069,000	$ 25,218,000
Total number of shares available for grant			2,033,272	3,000,000
Vesting period					4 years	4 years	3 years
Expiration period					10 years
RSU settlement to common stock upon vesting						1		1
Debt, interest rate (in percent)									7.125%	7.125%	7.125%