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Income Taxes (Schedule of Deferred Tax Assets) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Deferred tax assets: |  |
Net operating loss carryovers | $ 84,651 | $ 75,011
Stock compensation and other | 1,946 | 2,399
Change in fair value of warrant liabilities | 59 | 59
Amortization of license | 11,856 | 13,375
Lease liability | 929 | 1,466
Accruals and reserves | 1,841 | 1,434
Startup costs | 5 | 6
Tax credits | 18,189 | 15,649
174 Capitalization | 28,800 | 19,787
Total deferred tax assets | 148,276 | 129,186
Less valuation allowance | (147,694) | (128,101)
Net deferred tax assets | 582 | 1,085
Deferred tax liabilities: |  |
Right of use asset | (582) | (1,085)
Total deferred tax assets, net | $ 0 | $ 0

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