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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

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