Segment Information - Schedule of Financial Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Net revenues	$ 9,296	$ 3,786	$ 36,088	$ 10,659
Cost of revenues	3,883	3,602	7,646	6,407
Direct expenses	16,565	16,212	56,143	92,565
Segment contribution	(11,152)	(16,028)	(27,701)	(88,313)
Indirect expenses	375	83,228	1,377	117,289
Loss from operations	(11,527)	(99,256)	(29,078)	(205,602)
Components of other
Change in fair value of contingent consideration liability	0	0	0	(104,339)
Change in fair value of contingent stock consideration				(159)
Goodwill impairment	0	82,714	0	112,347
IPR&D impairment	0	0	0	107,800
Cell Therapy
Segment Reporting Information [Line Items]
Direct expenses	3,496	4,887	12,383	53,505
Segment contribution	(3,496)	(4,887)	(12,383)	(53,505)
Biobanking
Segment Reporting Information [Line Items]
Net revenues	1,292	1,427	3,857	4,062
Cost of revenues	238	398	952	1,355
Direct expenses	353	350	1,216	780
Segment contribution	701	679	1,689	1,927
Degenerative Disease
Segment Reporting Information [Line Items]
Net revenues	8,004	2,359	32,231	6,597
Cost of revenues	3,645	3,204	6,694	5,052
Direct expenses	4,187	1,901	14,385	6,799
Segment contribution	172	(2,746)	11,152	(5,254)
Other
Segment Reporting Information [Line Items]
Direct expenses	8,529	9,074	28,159	31,481
Segment contribution	(8,529)	(9,074)	(28,159)	(31,481)
Indirect expenses	375	83,228	1,377	117,289
Components of other
Change in fair value of contingent consideration liability				(104,339)
Change in fair value of contingent stock consideration		(39)		(159)
Goodwill impairment		82,714		112,347
IPR&D impairment				107,800
Amortization	375	553	1,377	1,640
Total other	$ 375	$ 83,228	$ 1,377	$ 117,289