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Note 11 - Recent Accounting and Reporting Developments (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2018
Income Tax Expense (Benefit)	$ (41)	$ (2,781)	$ (1,607)	$ (3,437)
Accounting Standards Update 2016-09 [Member]
Income Tax Expense (Benefit)			$ 800
Accounting Standards Update 2017-07 [Member] | Scenario, Forecast [Member] | Year Ended December 31, 2016 [Member] | Cost of Sales [Member]
Prior Period Reclassification Adjustment					$ (400)
Accounting Standards Update 2017-07 [Member] | Scenario, Forecast [Member] | Year Ended December 31, 2016 [Member] | Other Expense [Member]
Prior Period Reclassification Adjustment					$ 400

X

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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