QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jul. 28, 2012	Apr. 28, 2012	Jan. 28, 2012	Oct. 29, 2011	Jul. 30, 2011	Apr. 30, 2011	Jan. 29, 2011	Oct. 30, 2010	Jul. 28, 2012	Jul. 30, 2011	Jul. 31, 2010
QUARTERLY FINANCIAL DATA (UNAUDITED)
Net sales	$ 1,343,660	$ 1,388,023	$ 1,286,910	$ 1,217,428	$ 1,158,616	$ 1,203,983	$ 1,114,449	$ 1,052,967	$ 5,236,021	$ 4,530,015	$ 3,757,139
Gross profit	231,212	244,531	223,147	217,113	215,302	218,544	198,632	192,332	916,003	824,810	696,931
Income before income taxes	41,541	47,908	36,323	25,011	28,264	38,937	30,703	28,531	150,783	126,435	112,002
Net income	$ 25,142	$ 29,032	$ 22,011	$ 15,157	$ 17,178	$ 23,362	$ 18,729	$ 17,404	$ 91,342	$ 76,673	$ 68,321
Per common share income
Basic: (in dollars per share)	$ 0.51	$ 0.59	$ 0.45	$ 0.31	$ 0.35	$ 0.48	$ 0.39	$ 0.39	$ 1.87	$ 1.62
Diluted: (in dollars per share)	$ 0.51	$ 0.59	$ 0.45	$ 0.31	$ 0.35	$ 0.48	$ 0.39	$ 0.39	$ 1.86	$ 1.60
Weighted average basic Shares outstanding	48,951	48,848	48,774	48,594	48,484	48,406	48,232	44,771	48,766	47,459	43,184
Weighted average diluted shares of common stock	49,368	49,207	49,019	48,889	48,888	48,793	48,538	45,101	49,100	47,815	43,425
High
Per common share
Market Price, (in dollars per share)	$ 55.86	$ 50.37	$ 44.68	$ 42.53	$ 45.34	$ 46.05	$ 39.85	$ 37.48	$ 55.86	$ 46.05
Low
Per common share
Market Price, (in dollars per share)	$ 47.98	$ 43.81	$ 32.83	$ 35.07	$ 39.52	$ 36.71	$ 34.78	$ 32.65	$ 32.83	$ 32.65