Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017
Net revenue:
Product	$ 126,691	$ 130,330	$ 232,444	$ 250,582
Engineering	2,481	1,204	3,604	2,077
Total net revenue	129,172	131,534	236,048	252,659
Cost of sales:
Product	70,356	72,721	128,329	141,482
Engineering	1,952	1,123	3,088	1,846
Total cost of sales	72,308	73,844	131,417	143,328
Gross profit	56,864	57,690	104,631	109,331
Operating expenses:
Research and product development	15,631	16,213	30,642	32,063
Selling and marketing	13,195	17,358	25,601	35,538
General and administrative	12,098	3,979	24,039	17,600
Restructuring	197	267	731	299
Asset impairment charges		10,423		10,423
Total operating expenses	41,121	48,240	81,013	95,923
Income from operations	15,743	9,450	23,618	13,408
Other income (expense), net	939	28	1,175	(414)
Income before income taxes	16,682	9,478	24,793	12,994
Provision for income taxes	10,133	1,968	12,586	2,948
Net income	$ 6,549	$ 7,510	$ 12,207	$ 10,046
Net income per common share:
Basic	$ 0.52	$ 0.60	$ 0.98	$ 0.81
Diluted	$ 0.52	$ 0.59	$ 0.97	$ 0.79
Weighted average shares outstanding:
Basic	12,490	12,466	12,482	12,442
Diluted	12,601	12,680	12,606	12,712
Dividends declared and paid per share	$ 0.10	$ 0.10	$ 0.20	$ 0.20