Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data	3 Months Ended								12 Months Ended
	Jul. 29, 2011	Apr. 29, 2011	Jan. 28, 2011	Oct. 29, 2010	Jul. 30, 2010	Apr. 30, 2010	Jan. 29, 2010	Oct. 30, 2009	Jul. 29, 2011	Jul. 30, 2010	Jul. 31, 2009
Quarterly Financial Data (Unaudited) [Abstract]
Total revenue	$ 612,942	$ 582,525	$ 640,277	$ 598,691	$ 612,483	$ 578,233	$ 632,616	$ 581,183	$ 2,434,435	$ 2,404,515	$ 2,367,285
Gross profit	419,388	402,751	420,887	418,938	429,075	405,192	420,718	403,712	1,661,964	1,658,697	1,602,376
Income before income taxes	21,761	19,586	40,642	33,702	33,757	19,645	36,092	26,215	115,691	115,709	90,062
Income from continuing operations	17,543	15,154	28,777	23,734	27,413	14,428	25,393	18,024	85,208	85,258	65,957
Net income	$ 17,543	$ 15,154	$ 28,777	$ 23,734	$ 27,413	$ 14,428	$ 25,393	$ 18,024	$ 85,208	$ 85,258	$ 65,926
Income from continuing operations per share - basic	$ 0.77	$ 0.66	$ 1.24	$ 1.04	$ 1.18	$ 0.62	$ 1.11	$ 0.79	$ 3.70	$ 3.71	$ 2.94
Net income per share - basic	$ 0.77	$ 0.66	$ 1.24	$ 1.04	$ 1.18	$ 0.62	$ 1.11	$ 0.79	$ 3.70	$ 3.71	$ 2.94
Income from continuing operations per share - diluted	$ 0.75	$ 0.64	$ 1.20	$ 1.01	$ 1.14	$ 0.61	$ 1.09	$ 0.78	$ 3.61	$ 3.62	$ 2.89
Net income per share - diluted	$ 0.75	$ 0.64	$ 1.20	$ 1.01	$ 1.14	$ 0.61	$ 1.09	$ 0.78	$ 3.61	$ 3.62	$ 2.89