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Commitments and Contingencies - Narrative (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Commitments and Contingencies
Loss on abandonment of operating lease right-of-use asset	$ 0	$ 900,000	$ 0	$ 927,000	$ 0
Amount of gain (loss) recognized	400,000			600,000
Gain on sale of sale-leaseback				0	$ (82,000)
Loss contingency, estimate of possible loss	1,900,000			1,900,000
Penn | Penn License Agreement
Commitments and Contingencies
Annual payments to be made				25,000
Additional milestone payments for first CAR-M product				1,700,000
Penn | Penn License Agreement | Maximum
Commitments and Contingencies
Milestone payments	10,900,000			10,900,000
Additional milestone payments				30,000,000
Laboratory Equipment
Commitments and Contingencies
Gain (loss) on termination of finance lease recognized	$ 100,000			$ (1,700,000)

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