Quarterly Financial Data (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Data [Line Items]
Net sales	$ 22,326	$ 34,821	$ 36,797	$ 24,855	$ 19,875	$ 33,101	$ 35,565	$ 25,397	$ 118,799	$ 113,938	$ 113,521
Gross profit	3,318	6,610	6,970	4,215	2,703	6,099	7,138	4,202	21,113	20,142	17,302
Net earnings (loss)	$ (1,154)	$ 582	$ 787	$ (738)	$ (1,282)	$ 487	$ 1,097	$ (939)	$ (523)	$ (637)	$ (2,014)
Net earnings (loss) per share - diluted	$ (0.23)	$ 0.12	$ 0.16	$ (0.15)	$ (0.27)	$ 0.10	$ 0.23	$ (0.20)	$ (0.11)	$ (0.14)	$ (0.44)