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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands			12 Months Ended
	Jul. 25, 2019	Feb. 27, 2018	Dec. 31, 2019	Dec. 31, 2018
Recorded Unconditional Purchase Obligation [Line Items]
Restricted cash			$ 40
Initial term of lease			63 months
Buy-out of obligations lease		$ 600
Contractual obligation			$ 11,488	$ 2,750
Cell Therapy Business [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Sale of business month and year	2019-04
Cell Therapy Business [Member] | Tap Advisors LLC [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Payments for legal settlements			700
Cell Therapy Business [Member] | Tap Advisors LLC [Member] | Pending Litigation [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Loss contingency damages sought value	$ 3,700
Operating Lease Obligations [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Rent expense				$ 1,900
Pre-clinical Research Study Obligations [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Contractual obligation			$ 900
San Antonio, Texas [Member] | Office Laboratory and Storage Space [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating leases expiry year			2028

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+ References

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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