Quarterly Financial Information (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information (Unaudited)
Sales	$ 103,102	$ 79,783	$ 79,355	$ 67,219	$ 90,560	$ 82,883	$ 86,320	$ 74,650	$ 329,459	$ 334,413	$ 341,573
Gross profit	29,458	22,042	22,767	18,972	27,682	23,994	23,972	21,189	93,239	96,837	91,028
Income from continuing operations	1,312	2,541	2,691	452					4,395	17,855	11,986
Income from discontinued operations, net of tax	157	284	201						642
Income from operations					6,545	5,311	4,838	3,388	6,996	20,082	16,597
Gain from disposal of discontinued operation, net of tax	4,890								4,890
Net income	$ 6,143	$ 1,479	$ 2,265	$ 40	$ 7,752	$ 4,020	$ 3,640	$ 2,443	$ 9,927	$ 17,855	$ 11,986
Basic earnings per share:
Weighted average shares outstanding	12,160	11,721	11,663	11,660	11,574	11,567	11,562	11,524	11,801	11,557	11,463
Basic earnings per share from:
Continuing operations (in dollars per share)	$ 0.09	$ 0.10	$ 0.17						$ 0.37	$ 1.53	$ 1.03
Income from discontinued operations (in dollars per share)	$ 0.01	$ 0.03	$ 0.02						$ 0.06
Gain on disposal of discontinued operations (in dollars per share)	$ 0.40								$ 0.41
Basic earnings per share (in dollars per share)	$ 0.50	$ 0.13	$ 0.19		$ 0.67	$ 0.35	$ 0.31	$ 0.21	$ 0.84	$ 1.53	$ 1.03
Diluted earnings per share:
Weighted average shares outstanding	12,253	11,813	11,754	11,743	11,619	11,606	11,600	11,557	11,891	11,596	11,548
Diluted earnings per share from:
Continuing operations (in dollars per share)	$ 0.09	$ 0.10	$ 0.17						$ 0.37	$ 1.53	$ 1.02
Income from discontinued operations (in dollars per share)	$ 0.01	$ 0.03	$ 0.02						$ 0.05
Gain on disposal of discontinued operations (in dollars per share)	$ 0.40								$ 0.41
Diluted earnings per share (in dollars per share)	$ 0.50	$ 0.13	$ 0.19		$ 0.66	$ 0.34	$ 0.31	$ 0.21	$ 0.83	$ 1.53	$ 1.02