Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 24, 2016	Sep. 30, 2017	Sep. 24, 2016
Net sales	$ 93,651	$ 69,259	$ 268,614	$ 211,390
Cost and expenses:
Cost of sales	56,742	45,979	162,319	142,089
Research and development	9,609	8,673	28,851	24,698
Selling, general and administrative	16,882	13,701	47,362	41,990
	83,233	68,353	238,532	208,777
Income from operations	10,418	906	30,082	2,613
Interest and other, net	174	71	417	173
Income from continuing operations before taxes	10,592	977	30,499	2,786
Income tax provision	1,837	849	4,273	1,832
Income from continuing operations	8,755	128	26,226	954
Income (loss) from discontinued operations		51	(278)	(4)
Net income	$ 8,755	$ 179	$ 25,948	$ 950
Basic:
Income from continuing operations (in dollars per share)	$ 0.31	$ 0.01	$ 0.95	$ 0.04
Income (loss) from discontinued operations (in dollars per share)		0	(0.01)	0
Net income (in dollars per share)	0.31	0.01	0.94	0.04
Diluted:
Income from continuing operations (in dollars per share)	0.30	0.01	0.92	0.03
Income (loss) from discontinued operations (in dollars per share)		0	(0.01)	0
Net income (in dollars per share)	$ 0.30	$ 0.01	$ 0.91	$ 0.03
Weighted average shares used in computing income (loss) per share:
Basic (in shares)	28,155	26,761	27,614	26,596
Diluted (in shares)	29,105	27,367	28,640	27,382
Cash dividends declared per share (in dollars per share)	$ 0.06	$ 0.06	$ 0.18	$ 0.18