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Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Stock-based Compensation |  |
Weighted-average grant-date per share fair values granted (in USD per share) | $ 0.42 | $ 1.44
Stock-based options forfeited (in shares) | 3,037,128 |
Future compensation cost for awards not vested | $ 2.7 |
Weighted-average period compensation cost of unvested awards to be expensed (in years) | 1 year 9 months 18 days |
2014 Stock Incentive Plan |  |
Stock-based Compensation |  |
Terms (in years) | 4 years |
Vesting period (in years) | 4 years |
Shares available for issuance (in shares) | 7,700,000 |
2014 Employee Stock Purchase Plan |  |
Stock-based Compensation |  |
Shares available for issuance (in shares) | 200,000 |
Discount to the market price (as a percent) | 15.00% |
Cash Preservation Plan, 2025 |  |
Stock-based Compensation |  |
Stock-based options forfeited (in shares) | 3,000,000 |
Employee Stock Option | 2017 Stock Incentive Plan |  |
Stock-based Compensation |  |
Terms (in years) | 10 years |
Vesting period (in years) | 4 years |

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