Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Jul. 29, 2016	Apr. 29, 2016	Jan. 29, 2016	Oct. 30, 2015	Jul. 31, 2015	May 01, 2015	Jan. 30, 2015	Oct. 31, 2014	Jul. 29, 2016	Jul. 31, 2015	Aug. 01, 2014
Quarterly Financial Data (Unaudited) [Abstract]
Total revenue	$ 745,584	$ 700,136	$ 764,002	$ 702,629	$ 719,185	$ 683,705	$ 755,966	$ 683,428	$ 2,912,351	$ 2,842,284	$ 2,683,677
Store operating income	114,375	103,419	106,032	99,627	111,332	94,047	108,411	88,634	423,453	402,424	337,793
Income before income taxes	74,107	63,592	66,956	61,764	69,199	51,447	66,537	51,018	266,419	238,201	190,849
Net income	$ 51,023	$ 49,169	$ 48,242	$ 40,865	$ 47,399	$ 35,317	$ 47,163	$ 34,024	$ 189,299	$ 163,903	$ 132,128
Net income per share - basic (in dollars per share)	$ 2.13	$ 2.05	$ 2.02	$ 1.71	$ 1.98	$ 1.48	$ 1.97	$ 1.43	$ 7.91	$ 6.85	$ 5.55
Net income per share - diluted (in dollars per share)	$ 2.12	$ 2.04	$ 2.01	$ 1.70	$ 1.97	$ 1.47	$ 1.96	$ 1.42	$ 7.86	$ 6.82	$ 5.51