Net Income Per Share and Weighted Average Shares (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 28, 2016	Oct. 30, 2015
Net Income Per Share and Weighted Average Shares [Abstract]
Net income per share numerator	$ 48,355	$ 40,865
Net income per share denominator [Abstract]
Weighted average shares (in shares)	24,001,708	23,956,554
Add potential dilution [Abstract]
Stock options, nonvested stock awards and units and MSU Grants (in shares)	97,305	116,498
Diluted weighted average shares (in shares)	24,099,013	24,073,052