Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Statement [Abstract]
Net sales	$ 83,496	$ 71,808
Cost of sales	54,545	46,771
Gross margin	28,951	25,037
Selling, engineering and administration	21,261	20,312
Operating earnings	7,690	4,725
Interest expense, net	291	248
Earnings before income taxes	7,399	4,477
Provision for income taxes	2,767	1,570
Net earnings	$ 4,632	$ 2,907
Earnings per share: (in dollars per share)
Basic	$ 0.33	$ 0.21
Diluted	$ 0.32	$ 0.20
Dividends declared per common share	$ 0.18	$ 0.17
Shares used in computation of earnings per share: (in shares)
Basic	14,240,220	14,145,406
Impact of dilutive securities	89,977	91,351
Diluted	14,330,197	14,236,757