Note 8 - Derivative Instruments - Fair Value of Forward and Put Option Contracts (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current derivatives assets	$ 9,923	$ 2,709
Contracts in liability position	(4,228)	(19,353)
Non-current derivatives assets	12,897	2,503
Derivatives liabilities	522	18,528
Contracts in liability position	(522)	(18,528)
Forward and Put Option Contracts [Member] \| Current Derivatives Assets [Member]
Current derivatives assets	8,800	0
Contracts in liability position	0	0
Net asset (liability)	8,800	0
Forward and Put Option Contracts [Member] \| Noncurrent Derivative Assets [Member]
Net asset (liability)	11,600	0
Non-current derivatives assets	11,600	0
Derivatives liabilities	0	0
Contracts in liability position	0	0
Forward and Put Option Contracts [Member] \| Current Derivative Liabilities [Member]
Current derivatives assets	0	700
Contracts in liability position	(3,900)	(20,100)
Net asset (liability)	(3,900)	(19,400)
Forward and Put Option Contracts [Member] \| Other Noncurrent Liabilities [Member]
Net asset (liability)	(400)	(18,500)
Non-current derivatives assets	0	400
Derivatives liabilities	400	18,900
Contracts in liability position	$ (400)	$ (18,900)

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=126966630&loc=d3e41228-113958

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