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Note 6 - Fair Value Measurements - Fair Value Assets by Investment Category (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Cash and Cash Equivalents [Member] |  |
Assets, fair value | $ 89,371 | $ 70,266
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 31,188 | 0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 639 |
Other Current Assets [Member] |  |
Assets, fair value | 3,293 | 101
Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 303 | 101
Other Current Assets [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 2,990 |
Cash [Member] | Cash and Cash Equivalents [Member] |  |
Assets, fair value | 57,544 | 70,266
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 | 31,188 | 0
Money Market Funds [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 0 | 101
Money Market Funds, Rabbi Trust [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 0 |
Money Market Funds, Rabbi Trust [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 303 |
Certificates of Deposit [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 639 |
Certificates of Deposit [Member] | Other Current Assets [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 2,990 |
Reported Value Measurement [Member] |  |
Assets, fair value | 92,664 | 70,367
Reported Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 31,491 | 101
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 3,629 |
Reported Value Measurement [Member] | Cash [Member] |  |
Assets, fair value | 57,544 | 70,266
Reported Value Measurement [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 31,188 | 101
Reported Value Measurement [Member] | Money Market Funds, Rabbi Trust [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 303 |
Reported Value Measurement [Member] | Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 3,629 |
Estimate of Fair Value Measurement [Member] |  |
Assets, fair value | 92,961 | 70,367
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 31,491 | 101
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 3,926 |
Estimate of Fair Value Measurement [Member] | Cash [Member] |  |
Assets, fair value | 57,544 | 70,266
Estimate of Fair Value Measurement [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 31,188 | $ 101
Estimate of Fair Value Measurement [Member] | Money Market Funds, Rabbi Trust [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 303 |
Estimate of Fair Value Measurement [Member] | Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | $ 3,926 |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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