Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Aug. 01, 2014	May 02, 2014	Jan. 31, 2014	Nov. 01, 2013	Aug. 02, 2013	May 03, 2013	Feb. 01, 2013	Nov. 02, 2012	Aug. 01, 2014	Aug. 02, 2013	Aug. 03, 2012
Quarterly Financial Data (Unaudited) [Abstract]
Total revenue	$ 692,747	$ 643,298	$ 698,491	$ 649,141	$ 674,101	$ 640,407	$ 702,671	$ 627,451	$ 2,683,677	$ 2,644,630	$ 2,580,195
Gross profit	470,440	441,791	455,476	443,212	463,444	438,425	458,484	429,593	1,810,919	1,789,946	1,752,711
Income before income taxes	55,898	40,886	54,235	39,830	50,304	33,978	46,904	34,596	190,849	165,782	146,288
Net income	$ 39,185	$ 28,728	$ 37,055	$ 27,160	$ 34,303	$ 24,602	$ 35,168	$ 23,192	$ 132,128	$ 117,265	$ 103,081
Net income per share - basic (in dollars per share)	$ 1.65	$ 1.21	$ 1.56	$ 1.14	$ 1.44	$ 1.04	$ 1.48	$ 0.98	$ 5.55	$ 4.95	$ 4.47
Net income per share - diluted (in dollars per share)	$ 1.63	$ 1.20	$ 1.55	$ 1.14	$ 1.43	$ 1.02	$ 1.47	$ 0.97	$ 5.51	$ 4.90	$ 4.40