Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 25, 2015	Jul. 26, 2014	Jul. 27, 2013
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount	$ 4,000
Current:
Federal	42,516	$ 27,161	$ 22,173
Foreign	502	416	406
State	6,998	5,087	2,702
Current	50,016	32,664	25,281
Deferred:
Federal	305	(5,706)	(2,866)
Foreign	268	0	6
State	671	(617)	590
Deferred	1,244	(6,323)	(2,270)
Total provision for income taxes	51,260	26,341	23,011
Income taxes receivable	2,100	2,200
Income taxes payable	8,916	5,223
Deferred tax assets:
Insurance and other reserves	31,222	26,964
Allowance for doubtful accounts and reserves	1,047	742
Net operating loss carryforwards	1,443	994
Stock-based compensation	5,149	5,402
Other	1,303	1,062
Total deferred tax assets	40,164	35,164
Valuation allowance	(870)	(878)
Deferred tax assets, net of valuation allowance	39,294	34,286
Deferred tax liabilities:
Property and equipment	34,702	32,164
Goodwill and intangibles	29,930	26,998
Other	1,420	553
Deferred tax liabilities	66,052	59,715
Net deferred tax liabilities	26,758	25,429
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory rate applied to pre-tax income	47,454	23,212	20,370
State taxes, net of federal tax benefit	5,159	2,863	2,271
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount	(1,220)	491	366
Non-taxable and non-deductible items, net	2,800
Change in accruals for uncertain tax positions	(74)	53	153
Other items, net	(59)	(278)	(149)
Total provision for income taxes	51,260	26,341	23,011
Payment of interest and penalties accrued	900	800
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	2,401	2,348	2,194
Additions based on tax positions related to the fiscal year	44	137	155
Additions (reductions) based on tax positions related to prior years	(98)	10	19
Reductions related to the expiration of statutes of limitation	(20)	(94)	(20)
Balance at end of year	$ 2,327	$ 2,401	$ 2,348