INCOME TAXES (Details) (USD $)	12 Months Ended
	Aug. 02, 2014	Aug. 03, 2013	Jul. 28, 2012
Income Tax Disclosure [Abstract]
Income before income taxes from U.S. operations	$ 201,100,000	$ 166,700,000	$ 142,200,000
Income before income taxes, foreign operations	6,300,000	7,400,000	8,600,000
Current
U.S. Federal	66,953,000	44,095,000	55,083,000
State & Local	12,660,000	13,366,000	9,002,000
Foreign	1,432,000	2,021,000	1,471,000
Total income tax expense	81,045,000	59,482,000	65,556,000
Deferred
U.S. Federal	(894,000)	7,029,000	(7,506,000)
State & Local	1,452,000	(364,000)	462,000
Foreign	323,000	115,000	929,000
Total income tax expense	881,000	6,780,000	(6,115,000)
Total
U.S. Federal	66,059,000	51,124,000	47,577,000
State & Local	14,112,000	13,002,000	9,464,000
Foreign	1,755,000	2,136,000	2,400,000
Total income tax expense	81,926,000	66,262,000	59,441,000
U.S. statutory income tax rate (as a percent)	35.00%	35.00%	35.00%
Income tax expense (benefit), income tax reconciliation
Computed expected tax expense	72,593,000	60,940,000	52,774,000
State and local income tax, net of Federal income tax benefit	9,135,000	7,501,000	6,152,000
Non-deductible expenses	1,333,000	1,516,000	1,260,000
Tax effect of share-based compensation	160,000	134,000	(140,000)
General business credits	(114,000)	(1,374,000)	(231,000)
Other, net	(1,181,000)	(2,455,000)	(374,000)
Total income tax expense	81,926,000	66,262,000	59,441,000
Allocation of total income tax expense (benefit)
Income tax expense	81,926,000	66,262,000	59,441,000
Stockholders' equity, difference between compensation expense for tax purposes and amounts recognized for financial statement purposes	(2,601,000)	(1,952,000)	(2,804,000)
Other comprehensive income	0	0	495,000
Total income tax expense	79,325,000	64,310,000	57,132,000
Deferred tax assets:
Inventories, principally due to additional costs inventoried for tax purposes	7,532,000	6,906,000
Compensation and benefits related	24,129,000	21,224,000
Accounts receivable, principally due to allowances for uncollectible accounts	3,000,000	3,861,000
Accrued expenses	10,438,000	8,914,000
Net operating loss carryforwards	1,295,000	2,374,000
Other deferred tax assets	21,000	179,000
Total gross deferred tax assets	46,415,000	43,458,000
Less valuation allowance	0	819,000
Net deferred tax assets	46,415,000	42,639,000
Deferred tax liabilities:
Plant and equipment, principally due to differences in depreciation	36,494,000	34,222,000
Intangible assets	28,124,000	25,766,000
Other	274,000	303,000
Total deferred tax liabilities	64,892,000	60,291,000
Net deferred tax liabilities	(18,477,000)	(17,652,000)
Current deferred income tax assets	32,518,000	23,822,000
Non-current deferred income tax liabilities	(50,995,000)	(41,474,000)
Net deferred tax liabilities	(18,477,000)	(17,652,000)
Net increase (decrease) in total valuation allowance	$ 819,000	$ 171,000	$ 4,081,000