v3.23.2

Note 2 - Investments and Fair Value Measurement - Fair Value of Financial Assets and Liabilities by Level Within Fair Value Hierarchy (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Assets, fair value | $ 7,495 | $ 50,187
Liabilities, fair value | 7,098 |
Warrant Liability [Member] |  |
Liabilities, fair value | 7,098 |
Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 321 | 2,822
Liabilities, fair value | 0 |
Fair Value, Inputs, Level 1 [Member] | Warrant Liability [Member] |  |
Liabilities, fair value | 0 |
Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 7,174 | 47,365
Liabilities, fair value | 0 |
Fair Value, Inputs, Level 2 [Member] | Warrant Liability [Member] |  |
Liabilities, fair value | 0 |
Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value | 0 | 0
Liabilities, fair value | 7,098 |
Fair Value, Inputs, Level 3 [Member] | Warrant Liability [Member] |  |
Liabilities, fair value | 7,098 |
Money Market Funds [Member] |  |
Assets, fair value | 321 | 2,822
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 321 | 2,822
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 0 | 0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value | 0 | 0
US Government Agencies Debt Securities [Member] |  |
Assets, fair value | 2,444 |
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 0 |
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 2,444 |
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value | 0 |
Commercial Paper [Member] |  |
Assets, fair value | 4,730 | 37,902
Commercial Paper [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value | 0 | 0
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 4,730 | 37,902
Commercial Paper [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value | $ 0 | 0
Corporate Debt Securities [Member] |  |
Assets, fair value |  | 9,463
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value |  | 0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value |  | 9,463
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value |  | $ 0

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