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Note 4 - Fair-value Measurements - Fair Value Hierarchy (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | May 15, 2025 | May 14, 2025 | Dec. 31, 2024
--- | --- | --- | --- | ---
The 2029 Notes [Member] |  |  |  |  |
Embedded derivative |  | $ (15,020) |  |  |
The 2029 Notes [Member] | Conversion Option Derivative [Member] |  |  |  |  |
Embedded derivative |  | (15,000) | $ (23,000) | $ (23,000) |
Fair Value, Recurring [Member] |  |  |  |  |
Total Assets |  | 27,894 |  |  | $ 87,786
Share-settled liability |  | (7,627) |  |  |
Total Liabilities |  |  |  |  | 235
Total Liabilities |  | (22,534) |  |  |
Fair Value, Recurring [Member] | The Credit and Guaranty Agreement [Member] | Initial Term Loan [Member] | Call and Put Options Derivative [Member] |  |  |  |  |
Embedded derivative | [1] |  |  |  | 235
Embedded derivative | [2] | 113 |  |  |
Fair Value, Recurring [Member] | The 2029 Notes [Member] | Conversion Option Derivative [Member] |  |  |  |  |
Embedded derivative |  | (15,020) |  |  |
Certificates of Deposit [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Certificate of deposit classified as non-current restricted investments |  | 1,054 |  |  | 1,054
Money Market Funds [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Money-market funds |  | 26,840 |  |  | 86,732
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Total Assets |  | 27,894 |  |  | 87,786
Share-settled liability |  | 0 |  |  |
Total Liabilities |  |  |  |  | 0
Total Liabilities |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | The Credit and Guaranty Agreement [Member] | Initial Term Loan [Member] | Call and Put Options Derivative [Member] |  |  |  |  |
Embedded derivative | [1] |  |  |  | 0
Embedded derivative | [2] | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | The 2029 Notes [Member] | Conversion Option Derivative [Member] |  |  |  |  |
Embedded derivative |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Certificates of Deposit [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Certificate of deposit classified as non-current restricted investments |  | 1,054 |  |  | 1,054
Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Money-market funds |  | 26,840 |  |  | 86,732
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Total Assets |  | 0 |  |  | 0
Share-settled liability |  | (7,627) |  |  |
Total Liabilities |  |  |  |  | 235
Total Liabilities |  | (22,534) |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | The Credit and Guaranty Agreement [Member] | Initial Term Loan [Member] | Call and Put Options Derivative [Member] |  |  |  |  |
Embedded derivative | [1] |  |  |  | 235
Embedded derivative | [2] | 113 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | The 2029 Notes [Member] | Conversion Option Derivative [Member] |  |  |  |  |
Embedded derivative |  | (15,020) |  |  |
Fair Value, Inputs, Level 3 [Member] | Certificates of Deposit [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Certificate of deposit classified as non-current restricted investments |  | 0 |  |  | 0
Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member] | Fair Value, Recurring [Member] |  |  |  |  |
Money-market funds |  | $ 0 |  |  | $ 0
[1] | While the Term Loan is recorded as a liability, the embedded call and put options that have been identified as requiring bifurcation are recognized as a net embedded derivative asset reflected as a component of the Term Loan on the balance sheet.
[2] | While the Term Loan is recorded as a liability, the embedded call and put options that have been identified as requiring bifurcation are recognized as a net embedded derivative asset reflected as a component of the Term Loan on the balance sheet.

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