CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($)	3 Months Ended		6 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Net sales
Product sales	$ 163,904,000	$ 138,702,000	$ 330,805,000	$ 272,508,000
Product service	20,913,000	19,569,000	41,737,000	39,542,000
Total net sales	184,817,000	158,271,000	372,542,000	312,050,000
Cost of sales
Product sales	81,755,000	72,979,000	165,371,000	142,120,000
Product service	14,585,000	12,955,000	29,187,000	26,395,000
Total cost of sales	96,340,000	85,934,000	194,558,000	168,515,000
Gross profit	88,477,000	72,337,000	177,984,000	143,535,000
Expenses:
Selling	26,910,000	22,620,000	54,803,000	44,080,000
General and administrative	28,465,000	22,252,000	58,468,000	44,449,000
Research and development	4,489,000	3,069,000	9,037,000	6,834,000
Total operating expenses	59,864,000	47,941,000	122,308,000	95,363,000
Income from operations	28,613,000	24,396,000	55,676,000	48,172,000
Interest expense	1,145,000	893,000	2,257,000	1,659,000
Interest income	(19,000)	(22,000)	(38,000)	(43,000)
Income before income taxes	27,487,000	23,525,000	53,457,000	46,556,000
Income taxes	9,417,000	8,136,000	16,587,000	16,913,000
Net income	$ 18,070,000	$ 15,389,000	$ 36,870,000	$ 29,643,000
Earnings per common share:
Basic (in dollars per share)	$ 0.43	$ 0.37	$ 0.88	$ 0.71
Diluted (in dollars per share)	$ 0.43	$ 0.37	0.88	0.71
Dividends per common share (in dollars per share)			$ 0.07	$ 0.06