CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets (Note 5)
Accounts receivable, reserve	$ 324	$ 372
Inventories, obsolescence reserve	1,365us-gaap_InventoryValuationReserves	1,366us-gaap_InventoryValuationReserves
Property and equipment, accumulated depreciation	$ 26,470	$ 25,990

Amount of valuation reserve for inventory.

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

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