The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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Note 3 - Accounting Policies (Details Textual) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Cumulative Effect of New Accounting Principle in Period of Adoption					$ 1,573
Revenue from Contract with Customer, Including Assessed Tax		$ 31,602	$ 11,567
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance		34,065		$ 25,503
Cost of Goods and Services Sold, Total		$ 14,962	$ 3,133
Accounting Standards Update 2014-09 [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,900
Cost of Goods and Services Sold, Total	200
Accounting Standards Update 2014-09 [Member] \| Product Sales Allowance [Member]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance	1,100
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption					$ 1,573
Retained Earnings [Member] \| Accounting Standards Update 2014-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 1,600