Note 13 - Segment Reporting - Income From Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Segment profit	$ 9,469	$ 7,443
Selling, general and administrative expense	(5,225)	(4,392)
Patent litigation defense costs	(80)	(129)
Severance and transition costs	(633)	(784)
Gain (loss) from disposal of equipment	108	(62)
Depreciation and amortization	(5,989)	(5,833)
Loss from Operations	$ (2,350)	$ (3,757)

The amount of expense associated with severance and transition costs.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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The net result for the period of deducting operating expenses from operating revenues.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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