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Note 6 - Fair Value Measurements - Fair Value Assets by Investment Category (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Cash and Cash Equivalents [Member]
Assets, fair value	$ 65,927	$ 68,253
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	1	1
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	984	1,335
Other Current Assets [Member]
Assets, fair value	2,294	2,168
Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	386	566
Other Current Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	1,908	1,602
Cash [Member] | Cash and Cash Equivalents [Member]
Assets, fair value	64,942	66,917
Cash [Member] | Other Current Assets [Member]
Assets, fair value	0	0
Money Market Funds [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	1	1
Money Market Funds [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	0	0
Money Market Funds, Rabbi Trust [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	0	0
Money Market Funds, Rabbi Trust [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	386	566
Certificates of Deposit [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	984	1,335
Certificates of Deposit [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	1,908	1,602
Reported Value Measurement [Member]
Assets, fair value	68,221	70,422
Reported Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	387	567
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	2,892	2,938
Reported Value Measurement [Member] | Cash [Member]
Assets, fair value	64,942	66,917
Reported Value Measurement [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	1	1
Reported Value Measurement [Member] | Money Market Funds, Rabbi Trust [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	386	566
Reported Value Measurement [Member] | Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	2,892	2,938
Estimate of Fair Value Measurement [Member]
Assets, fair value	68,679	70,832
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	387	567
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	3,350	3,348
Estimate of Fair Value Measurement [Member] | Cash [Member]
Assets, fair value	64,942	66,917
Estimate of Fair Value Measurement [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	1	1
Estimate of Fair Value Measurement [Member] | Money Market Funds, Rabbi Trust [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	386	566
Estimate of Fair Value Measurement [Member] | Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	$ 3,350	$ 3,348

X

- Definition

Fair value portion of asset recognized for present right to economic benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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