Consolidated Statements of Income - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Net sales	$ 49,675,000	$ 50,725,000	$ 147,078,000	$ 151,140,000
Cost and expenses:
Cost of products sold	33,340,000	34,326,000	98,526,000	101,696,000
Engineering and product development	2,339,000	2,908,000	7,509,000	8,442,000
Selling, general and administrative	9,244,000	8,730,000	25,897,000	24,005,000
Depreciation and amortization	847,000	579,000	2,065,000	1,608,000
Restructuring charges	223,000		223,000	463,000
Total cost and expenses	45,993,000	46,543,000	134,220,000	136,214,000
Income from operations	3,682,000	4,182,000	12,858,000	14,926,000
Other income (expense):
Amortization of deferred financing costs	(59,000)	(22,000)	(119,000)	(65,000)
Interest income	2,000	2,000	23,000	5,000
Interest expense	(52,000)	(7,000)	(63,000)	(21,000)
Other gain (loss), net	(669,000)	56,000	(23,000)	1,535,000
Income from continuing operations before income taxes	2,904,000	4,211,000	12,676,000	16,380,000
Income tax provision	1,067,000	1,716,000	4,421,000	5,832,000
Income from continuing operations	1,837,000	2,495,000	8,255,000	10,548,000
(Loss) income from discontinued operations, net of tax	(700,000)	400,000	(1,005,000)	402,000
Net income	$ 1,137,000	$ 2,895,000	$ 7,250,000	$ 10,950,000
Basic net income (loss) per common share
Income from continuing operations	$ 0.46	$ 0.60	$ 2.06	$ 2.55
(Loss) income from discontinued operations, net of tax	(0.17)	0.10	(0.25)	0.10
Net income	0.29	0.70	1.81	2.65
Diluted net income (loss) per common share
Income from continuing operations	0.46	0.59	2.03	2.52
(Loss) income from discontinued operations, net of tax	(0.17)	0.10	(0.24)	0.10
Net income	$ 0.29	$ 0.69	$ 1.79	$ 2.62
Shares used in computing basic net income (loss) per common share	3,960,000	4,145,000	4,015,000	4,137,000
Shares used in computing diluted net income (loss) per common share	3,989,000	4,204,000	4,059,000	4,178,000