Note 8 - Fair Value Measurements - Minimum Assessment Agreements (Details) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Obligation under assessment arrangements	$ 23,311	$ 24,306
Reported Value Measurement [Member]
Obligation under assessment arrangements	20,032	20,734
Estimate of Fair Value Measurement [Member]
Obligation under assessment arrangements	$ 26,748	$ 26,908

Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_CommitmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant