Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]
Net sales	$ 334,122	$ 319,660	$ 262,915
Cost of sales	217,133	197,414	173,095
Gross margin	116,989	122,246	89,820
Selling, engineering and administration	77,882	77,777	62,286
Operating earnings	39,107	44,469	27,534
Interest expense, net	1,098	998	185
Earnings before income taxes	38,009	43,471	27,349
Provision for income taxes	13,392	15,439	8,188
Net earnings	$ 24,617	$ 28,032	$ 19,161
Basic
from continuing operations (in dollars per share)	$ 1.71	$ 1.96	$ 1.28
Diluted:
from continuing operations (in dollars per share)	$ 1.70	$ 1.95	$ 1.27
Shares used in computation of earnings per share:
Basic (in shares)	14,362	14,332	14,971
Impact of dilutive securities (in shares)	78	67	78
Diluted (in shares)	14,440	14,399	15,049