Net Income Per Share and Weighted Average Shares (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Oct. 31, 2014	Nov. 01, 2013
Net Income Per Share and Weighted Average Shares [Abstract]
Net income per share numerator	$ 34,024	$ 27,160
Net income per share denominator [Abstract]
Weighted average shares (in shares)	23,862,195	23,817,436
Add potential dilution [Abstract]
Stock options, nonvested stock awards and MSU Grants (in shares)	139,243	107,652
Diluted weighted average shares (in shares)	24,001,438	23,925,088