Inventories (Details) (USD $)	Sep. 30, 2012	Dec. 31, 2011
Inventory Disclosure [Abstract]
Finished goods	$ 15,036,000	$ 9,832,000
Parts and components	1,864,000	1,769,000
Total inventories	16,900,000	11,601,000
Valuation allowances	$ 800,000	$ 1,000,000