Note 8 - Derivative Instruments - Fair Value of Forward and Put Option Contracts (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Contracts in asset position	$ 7,195	$ 3,470
Contracts in liability position	(3,906)	(11,737)
Contracts in asset position	6,346	4,558
Forward and Put Option Contracts [Member] \| Current Derivatives Assets [Member]
Contracts in asset position	3,300	200
Contracts in liability position	(1,100)	(200)
Net asset (liability)	2,200	0
Forward and Put Option Contracts [Member] \| Noncurrent Derivative Assets [Member]
Net asset (liability)	2,100	400
Contracts in asset position	2,300	500
Contracts in liability position	(200)	(100)
Forward and Put Option Contracts [Member] \| Current Derivative Liabilities [Member]
Contracts in asset position	0	100
Contracts in liability position	(3,900)	(11,800)
Net asset (liability)	(3,900)	(11,700)
Forward and Put Option Contracts [Member] \| Other Noncurrent Liabilities [Member]
Net asset (liability)	(800)	0
Contracts in asset position	400	0
Contracts in liability position	$ (1,200)	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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