CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets (Note 5)
Accounts receivable, reserve	$ 369	$ 321
Inventories, obsolescence reserve	417	417
Property and equipment, accumulated depreciation	$ 24,775	$ 24,316

Amount of valuation reserve for inventory.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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