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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

X

- 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

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X

- 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

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- Details

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Data Type:	na
Balance Type:
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