Segment Information - Financial Data by Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Sales to external customers	$ 22,135	$ 20,363	$ 68,198	$ 64,835
Operating income (loss)	1,409	1,359	5,115	4,895
Interest expense, net	99	83	242	200
Other expense (income), net	(13)	7	15	93
Consolidated income before income taxes	1,323	1,269	4,858	4,602
Assets	70,738		70,738		67,828
United States
Sales to external customers	18,273	16,541	55,992	51,702
Operating income (loss)	1,183	1,240	4,454	3,992
Assets	59,745		59,745		56,115
Canada
Sales to external customers	1,782	2,170	6,549	7,137
Operating income (loss)	130	182	592	753
Assets	5,762		5,762		6,107
Europe
Sales to external customers	2,080	1,652	5,657	5,996
Operating income (loss)	96	(63)	69	149
Assets	$ 5,231		$ 5,231		$ 5,606