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Income Taxes - Components Of Deferred Tax Asset Balances (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Deferred tax assets: |  |
Net operating losses | $ 21,573 | $ 10,519
Tax credits | 17,407 | 6,243
Research and development capitalization | 74,211 | 39,059
Accruals and reserves | 115 | 15
Stock-based compensation | 3,088 | 1,361
Operating lease liabilities | 6,452 | 6,842
Other capitalized expenses | 11,832 | 4,567
Gross deferred tax assets | 134,678 | 68,606
Valuation allowance | (127,990) | (61,404)
Deferred tax assets, net of valuation allowance | 6,688 | 7,202
Deferred tax liabilities: |  |
Fixed assets | (885) | (1,025)
Operating lease right-of-use assets | (5,803) | (6,177)
Deferred tax liabilities | (6,688) | (7,202)
Increase in valuation allowance | $ 66,600 | $ 35,400

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