Note 5 - Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Other Long-term Assets [Member]
Operating lease ROU assets	$ 6,470	$ 6,297
Other Accrued Liabilities [Member]
Operating lease liabilities	2,530	2,539
Other Long-term Liabilities [Member]
Operating Lease, Liability, Noncurrent	$ 3,242	$ 3,268

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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