Note 2 - Business Segments and Sales of Products (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)
Number of Reportable Segments			5
Derivative, Gain (Loss) on Derivative, Net, Total			$ (2,116)	$ (11,188)
Financially-settled Forward Contracts [Member]
Derivative, Gain (Loss) on Derivative, Net, Total	$ 3,300	$ 5,000	$ 500	$ 3,300

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8672-108599

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