Segment Information - Financial Data by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Sales to external customers	$ 29,903	$ 30,008	$ 86,694	$ 82,555
Operating income (loss)	1,991	1,930	6,693	6,289
Interest expense, net	149	153	420	343
Other expense (income), net	92	67	149	78
Consolidated income before income taxes	1,750	1,710	6,124	5,868
Assets	86,585		86,585		$ 79,308
United States
Sales to external customers	26,160	25,833	75,943	69,946
Operating income (loss)	1,849	1,819	6,405	5,752
Assets	78,458		78,458		70,526
Canada
Sales to external customers	1,669	2,190	5,726	7,372
Operating income (loss)	30	94	202	652
Assets	4,102		4,102		4,363
Europe
Sales to external customers	2,074	1,985	5,025	5,237
Operating income (loss)	112	$ 17	86	$ (115)
Assets	$ 4,025		$ 4,025		$ 4,419