Net Income Per Share and Weighted Average Shares (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 28, 2017	Apr. 29, 2016	Apr. 28, 2017	Apr. 29, 2016
Net Income Per Share and Weighted Average Shares [Abstract]
Net income per share numerator	$ 46,924	$ 49,169	$ 148,006	$ 138,276
Net income per share denominator [Abstract]
Weighted average shares (in shares)	24,042,573	23,941,188	24,028,175	23,945,184
Add potential dilution [Abstract]
Stock options, nonvested stock awards and MSU Grants (in shares)	78,630	132,590	83,578	119,440
Diluted weighted average shares (in shares)	24,121,203	24,073,778	24,111,753	24,064,624