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Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Assets
Short-term investments	$ 0	$ 100,000	$ 100,000
Liabilities
Warrant liability	16,929		81,283
Fair Value, Recurring
Assets
Total assets	192,222		200,972
Liabilities
Total liabilities	16,984		83,241
Level 1 | Fair Value, Recurring
Assets
Available-for-sale investments	192,222		100,972
Level 1 | Fair Value, Recurring | Public Warrants
Liabilities
Warrant liability	6,465		31,034
Level 2 | Fair Value, Recurring
Assets
Short-term investments	0		100,000
Level 3 | Fair Value, Recurring
Liabilities
Earnout Shares	55		1,958
Level 3 | Fair Value, Recurring | Private Placement Warrants
Liabilities
Warrant liability	$ 10,464		$ 50,249

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