Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Inventory [Line Items]
Finished systems	$ 0	$ 24
Raw materials and service parts	655	927
Work in progress	197	40
Inventory, Gross, Total	852	991
Less: Reserve for obsolete inventory	(444)	(444)
Inventory, net	$ 408	$ 547

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