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Notes Payable (Narrative) (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | ---
Apr. 11, 2023 | Mar. 04, 2022 | Jun. 30, 2024 | Jun. 30, 2023 | Mar. 31, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Interest expense |  |  | $ 2 | $ 2,932 |  | $ 3 | $ 4,108
Amortization of debt discount |  |  |  |  |  | $ 0 | 118
Runway Debt Facility |  |  |  |  |  |  |
Payoff amount of debt facility | $ 30,400 |  |  |  |  |  |
Interest rate during period |  |  |  |  | 13.77% |  |
Interest expense |  |  |  | $ 300 |  |  | 1,300
Amortization of debt discount |  |  |  |  |  |  | $ 100
Runway Debt Facility | Minimum [Member] |  |  |  |  |  |  |
Variable interest rate floor (as a percent) |  | 9.25% |  |  |  |  |
Runway Debt Facility | Base Rate |  |  |  |  |  |  |
Variable interest rate floor (as a percent) |  | 8.75% |  |  |  |  |
Runway Debt Facility | Three month LIBOR |  |  |  |  |  |  |
Variable interest rate floor (as a percent) |  | 0.50% |  |  |  |  |

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