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Fair Value Measurements - Inputs (Details) $ / shares in Units, $ in Thousands	Sep. 30, 2023 USD ($) $ / shares Y	Apr. 19, 2022 USD ($)
Credit Agreement and Guaranty
Fair value inputs
Fair value debt	$ 56,151
Revenue Interest Financing Agreement
Fair value inputs
Fair value debt	$ 28,547
BTI Warrants
Fair value inputs
Fair value warrant classified as equity		$ 3,245
Fair value of grants per share \| $ / shares	$ 14.93
Strike price \| BTI Warrants
Fair value inputs
Derivative liability input \| $ / shares	20.04
Strike price \| Equity Investment Rights
Fair value inputs
Derivative liability input	1.100
Volatility (annual) \| BTI Warrants
Fair value inputs
Derivative liability input	0.95
Volatility (annual) \| Equity Investment Rights
Fair value inputs
Derivative liability input	0.979
Volatility (annual) \| OnkosXcel Warrants
Fair value inputs
Derivative liability input	1
Probability of exercise \| Equity Investment Rights
Fair value inputs
Derivative liability input	0.891
Time period \| BTI Warrants
Fair value inputs
Derivative liability input \| Y	7
Time period \| Equity Investment Rights
Fair value inputs
Derivative liability input \| Y	3.6
Estimated premium to 30-day average \| Equity Investment Rights
Fair value inputs
Derivative liability input	0.245
Discount rate \| Equity Investment Rights
Fair value inputs
Derivative liability input	0.051
Risk-free rate \| BTI Warrants
Fair value inputs
Derivative liability input	0.0295