CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME
Revenues	$ 403,516	$ 366,694	$ 371,084
Cost of goods sold	282,460	258,119	258,500
Gross profit	121,056	108,575	112,584
Operating costs and expenses:
Selling	17,249	15,392	16,536
General and administrative	42,419	38,301	37,688
Engineering and development	27,818	25,487	23,086
Business development	1,299	473	113
Amortization of intangible assets	6,245	5,928	5,718
Total operating costs and expenses	95,030	85,581	83,141
Operating income	26,026	22,994	29,443
Other expense, net:
Interest expense	3,236	3,716	5,134
Other (income) expense, net	(323)	502	468
Total other expense, net	2,913	4,218	5,602
Income before income taxes	23,113	18,776	23,841
Income tax benefit (provision)	981	(5,133)	(6,819)
Net income	$ 24,094	$ 13,643	$ 17,022
Basic earnings per share:
Earnings per share	$ 1.67	$ 0.96	$ 1.21
Basic weighted average common shares	14,413	14,243	14,097
Diluted earnings per share:
Earnings per share	$ 1.66	$ 0.95	$ 1.20
Diluted weighted average common shares	14,517	14,333	14,192
Net income	$ 24,094	$ 13,643	$ 17,022
Other comprehensive income:
Foreign currency translation adjustment	(7,193)	8,410	(680)
Change in accumulated income (loss) on derivatives	1,618	(1,161)	(711)
Pension adjustments	770	(5)	(622)
Comprehensive income	$ 19,289	$ 20,887	$ 15,009