Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Net sales	$ 100,570	$ 83,644
Cost of sales	61,559	53,569
Gross margin	39,011	30,075
Selling, engineering and administration	26,205	23,022
Operating earnings	12,806	7,053
Interest expense, net	270	317
Earnings before income taxes	12,536	6,736
Provision for income taxes	4,546	2,509
Net earnings	$ 7,990	$ 4,227
Earnings per share:
Basic (in dollars per share)	$ 0.55	$ 0.29
Diluted (in dollars per share)	0.55	0.29
Dividends declared per common share (in dollars per share)	$ 0.20	$ 0.19
Shares used in computation of earnings per share:
Basic (in shares)	14,421,250	14,332,775
Impact of dilutive securities (in shares)	77,432	74,232
Diluted (in shares)	14,498,682	14,407,007