Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Inventory [Line Items]
Finished systems	$ 310	$ 385
Raw materials and service parts	698	756
Work in progress	0	90
Inventory, Gross, Total	1,008	1,231
Less: Reserve for obsolete inventory	(457)	(490)
Inventory, net	$ 551	$ 741

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Certain changes made in the current period to the value and amount of inventory reported.

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Amount before last-in first-out (LIFO) and valuation reserves of merchandise or goods held by the entity that are readily available for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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Gross amount of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

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Gross amount of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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