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Fair Value Measurements - Hierarchy (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 25, 2024	Dec. 31, 2023
Fair value assets and liabilities
Warrant derivative liability	$ 9,186		$ 1,905
Warrants 2024, Accompanying Warrants
Fair value assets and liabilities
Warrant derivative liability	7,626	$ 19,347
Level 1
Fair value assets and liabilities
Fair value money market accounts	52,061		$ 64,860
Recurring
Fair value assets and liabilities
Warrant derivative liability	9,186
Recurring \| Equity Investment Rights
Fair value assets and liabilities
Warrant derivative liability	1,327
Recurring \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	233
Recurring \| Warrants 2024, Accompanying Warrants
Fair value assets and liabilities
Warrant derivative liability	7,626
Recurring \| Level 2
Fair value assets and liabilities
Warrant derivative liability	7,626
Recurring \| Level 2 \| Warrants 2024, Accompanying Warrants
Fair value assets and liabilities
Warrant derivative liability	7,626
Recurring \| Level 3
Fair value assets and liabilities
Warrant derivative liability	1,560
Recurring \| Level 3 \| Equity Investment Rights
Fair value assets and liabilities
Warrant derivative liability	1,327
Recurring \| Level 3 \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	233
Recurring \| Fair Value
Fair value assets and liabilities
Warrant derivative liability	9,186
Recurring \| Fair Value \| Equity Investment Rights
Fair value assets and liabilities
Warrant derivative liability	1,327
Recurring \| Fair Value \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	233
Recurring \| Fair Value \| Warrants 2024, Accompanying Warrants
Fair value assets and liabilities
Warrant derivative liability	$ 7,626