SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	12 Months Ended
Jul. 30, 2011 year quarter month plan weeks	Jul. 31, 2010 weeks	Aug. 01, 2009 weeks
Basis of Presentation
Weeks in a fiscal year (in weeks)	52	52	52
Weeks in interim quarter (in weeks)	13	13	13
Cash Equivalents
Maximum original maturity of securities to be classified as cash equivalents (in months)	3
Property and equipment
Interest capitalized		$ 100,000	$ 300,000
Property and equipment
Property and equipment, gross	457,518,000	437,065,000
Less accumulated depreciation and amortization	172,367,000	157,810,000
Net property and equipment	285,151,000	279,255,000
Depreciation expense	31,100,000	25,000,000	24,100,000
Land
Property and equipment
Property and equipment, gross	13,241,000	14,944,000
Buildings and improvements
Property and equipment
Original Estimated Useful Lives (Years), minimum	20	20
Original Estimated Useful Lives (Years), maximum	40	40
Property and equipment, gross	158,790,000	166,235,000
Leasehold improvements
Property and equipment
Original Estimated Useful Lives (Years), minimum	5	5
Original Estimated Useful Lives (Years), maximum	20	20
Property and equipment, gross	77,605,000	58,740,000
Warehouse equipment
Property and equipment
Original Estimated Useful Lives (Years), minimum	3	3
Original Estimated Useful Lives (Years), maximum	30	30
Property and equipment, gross	88,643,000	88,720,000
Office equipment
Property and equipment
Original Estimated Useful Lives (Years), minimum	3	3
Original Estimated Useful Lives (Years), maximum	10	10
Property and equipment, gross	58,643,000	49,305,000
Computer software
Property and equipment
Original Estimated Useful Lives (Years), minimum	3	3
Original Estimated Useful Lives (Years), maximum	7	7
Property and equipment, gross	40,986,000	18,104,000
Motor vehicles
Property and equipment
Original Estimated Useful Lives (Years), minimum	3	3
Original Estimated Useful Lives (Years), maximum	7	7
Property and equipment, gross	4,182,000	4,602,000
Construction in progress
Property and equipment
Property and equipment, gross	$ 15,428,000	$ 36,415,000

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The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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