Quarterly Results of Operations (Unaudited)- Quarterly Results of Operations (Detail) (USD $)	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
Schedule Of Quarterly Financial Information [Line Items]
Net sales	$ 22,300,000	$ 24,200,000	$ 24,000,000	$ 21,500,000	$ 19,300,000	$ 21,300,000	$ 22,200,000	$ 20,400,000	$ 92,045,000	$ 83,196,000	$ 79,815,000
Gross profit	6,500,000	7,500,000	7,600,000	6,000,000	5,500,000	6,300,000	6,500,000	6,000,000	27,574,000	24,327,000	24,107,000
Operating income	2,000,000	3,000,000	2,900,000	1,400,000		1,600,000	2,200,000	1,600,000	9,328,000	5,418,000	6,412,000
Income from continuing operations					600,000	800,000	1,200,000	900,000
Discontinued operations					28,100,000	1,800,000	900,000	600,000
Net income	$ 1,300,000	$ 2,000,000	$ 1,800,000	$ 900,000	$ 28,700,000	$ 2,600,000	$ 2,100,000	$ 1,500,000	$ 6,015,000	$ 34,961,000	$ 7,673,000
Basic and diluted earnings per share:
Continuing operations					$ 0.05	$ 0.07	$ 0.10	$ 0.07	$ 0.49	$ 0.28	$ 0.28
Discontinued operations					$ 2.27	$ 0.14	$ 0.07	$ 0.05		$ 0.31	$ 0.34
Net income	$ 0.11	$ 0.16	$ 0.15	$ 0.07	$ 2.32	$ 0.21	$ 0.17	$ 0.12	$ 0.49	$ 2.82	$ 0.62