Segment Information (Continuing Operating Segments) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($) segment	Dec. 31, 2015 USD ($)
Net revenues	$ 1,716	$ 1,885
Interest income	11	1
Depreciation and amortization	79	88
Interest expense	1	4
Purchase of property and equipment	0	5
Total assets	12,986		$ 13,421
Income (loss) before income taxes	$ (135)	$ 848
Number of reportable segments \| segment	1	2
Production Monitoring [Member]
Net revenues	$ 1,716	$ 1,885
Income (loss) before income taxes	(135)	32
Segment Investments [Member]
Income (loss) before income taxes	$ 0	$ 816

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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