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Note 5 - Property and Equipment (Details Textual) - USD ($) $ in Thousands | 1 Months Ended | 9 Months Ended
--- | --- | ---
Aug. 31, 2018 | Sep. 30, 2018 | Sep. 30, 2017
Proceeds from Sale of Property, Plant, and Equipment, Total |  | $ 5,954 | $ 146
Gain (Loss) on Disposition of Property Plant Equipment, Total |  | $ 2,536 | $ 69
Property in Houston, Texas [Member] |  |  |
Proceeds from Sale of Property, Plant, and Equipment, Total | $ 5,800 |  |
Gain (Loss) on Disposition of Property Plant Equipment, Total | $ 2,800 |  |

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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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- Definition The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details
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