CONSOLIDATED STATMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 27, 2018	Jan. 28, 2017	Jan. 27, 2018	Jan. 28, 2017
Sales	$ 417,382	$ 412,215	$ 803,856	$ 801,907
Cost of sales	305,097	300,977	587,691	586,021
Gross profit	112,285	111,238	216,165	215,886
Operating and administrative expense	96,066	94,393	188,358	185,524
Depreciation and amortization	6,386	6,233	12,621	12,296
Operating income	9,833	10,612	15,186	18,066
Interest expense	(1,102)	(1,114)	(2,207)	(2,230)
Interest income	864	648	1,764	1,335
Income before income taxes	9,595	10,146	14,743	17,171
Income taxes	84	4,154	2,215	7,070
Net income	$ 9,511	$ 5,992	$ 12,528	$ 10,101
Common Class A [Member]
Net income per share:
Basic (in dollars per share)	$ 0.74	$ 0.47	$ 0.97	$ 0.80
Diluted (in dollars per share)	0.66	0.42	0.87	0.71
Common Class B [Member]
Net income per share:
Basic (in dollars per share)	0.48	0.31	0.63	0.52
Diluted (in dollars per share)	$ 0.48	$ 0.31	$ 0.63	$ 0.52