CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Net sales	$ 276,665	$ 282,426	$ 563,612	$ 575,622
Cost of goods sold	137,538	142,616	283,080	289,273
Gross margin	139,127	139,810	280,532	286,349
Operating expenses:
Research and development	10,517	11,074	21,484	22,400
Selling, general and administrative	87,366	92,706	176,913	187,297
Total operating expenses	97,883	103,780	198,397	209,697
Operating income	41,244	36,030	82,135	76,652
Other income (expense):
Investment and other income	1,760	1,377	3,140	1,360
Interest expense	(647)	(717)	(1,348)	(1,429)
Income before income taxes	42,357	36,690	83,927	76,583
Income tax expense	8,804	7,463	12,876	16,719
Net income	$ 33,553	$ 29,227	$ 71,051	$ 59,864
Weighted average common shares outstanding:
Basic	53,320	52,532	53,232	52,366
Diluted	53,827	53,206	53,781	53,082
Class A nonvoting common stock
Earnings Per Share
Net earnings per share, basic	$ 0.63	$ 0.56	$ 1.33	$ 1.14
Net earnings per share, diluted	0.62	0.55	1.32	1.13
Dividends	0.22	0.21	0.44	0.43
Class B voting common stock
Earnings Per Share
Net earnings per share, basic	0.63	0.56	1.32	1.13
Net earnings per share, diluted	0.62	0.55	1.31	1.11
Dividends	$ 0.22	$ 0.21	$ 0.42	$ 0.41