Note 3. Inventories (Detail) (USD $)	Sep. 28, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 16,749,000	$ 16,239,000
Work in process	1,814,000	1,701,000
Finished goods	9,937,000	8,113,000
Total	$ 28,500,000	$ 26,053,000

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