SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 01, 2015	Aug. 02, 2014	Aug. 03, 2013
Basis of Presentation
Days in fiscal year	364 days	364 days	371 days
Days in interim quarter	91 days	91 days	98 days
Cash Equivalents
Maximum original maturity of securities to be classified as cash equivalents (in months)	3 months
Property and equipment
Interest capitalized	$ 500	$ 900	$ 0
Property and equipment
Property and equipment, gross	889,781	757,598
Less accumulated depreciation and amortization	317,329	273,638
Net property and equipment	572,452	483,960
Depreciation expense	55,000	42,900	$ 37,600
Land
Property and equipment
Property and equipment, gross	43,033	31,324
Buildings and improvements
Property and equipment
Property and equipment, gross	302,066	215,172
Leasehold improvements
Property and equipment
Property and equipment, gross	133,120	130,739
Warehouse equipment
Property and equipment
Property and equipment, gross	155,477	128,121
Office equipment
Property and equipment
Property and equipment, gross	57,519	71,524
Computer software
Property and equipment
Property and equipment, gross	130,652	97,196
Motor vehicles
Property and equipment
Property and equipment, gross	4,357	4,520
Construction in progress
Property and equipment
Property and equipment, gross	$ 63,557	$ 79,002
Minimum | Buildings and improvements
Property and equipment
Original estimated useful lives	20 years	20 years
Minimum | Leasehold improvements
Property and equipment
Original estimated useful lives	5 years	5 years
Minimum | Warehouse equipment
Property and equipment
Original estimated useful lives	3 years	3 years
Minimum | Office equipment
Property and equipment
Original estimated useful lives	3 years	3 years
Minimum | Computer software
Property and equipment
Original estimated useful lives	3 years	3 years
Minimum | Motor vehicles
Property and equipment
Original estimated useful lives	3 years	3 years
Maximum | Buildings and improvements
Property and equipment
Original estimated useful lives	40 years	40 years
Maximum | Leasehold improvements
Property and equipment
Original estimated useful lives	20 years	20 years
Maximum | Warehouse equipment
Property and equipment
Original estimated useful lives	30 years	30 years
Maximum | Office equipment
Property and equipment
Original estimated useful lives	10 years	10 years
Maximum | Computer software
Property and equipment
Original estimated useful lives	7 years	7 years
Maximum | Motor vehicles
Property and equipment
Original estimated useful lives	7 years	7 years