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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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