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Commitments and Contingencies - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Recorded Unconditional Purchase Obligation [Line Items] |  |
Restricted cash | $ 0 | $ 40,000
Security deposit | 0 |
Contractual obligation | 7,481,000 |
Operating Lease Obligations [Member] |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |
Rent expense | 200,000 | $ 700,000
Pre-clinical Research Study Obligations [Member] |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |
Contractual obligation | $ 0 |
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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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121573735&loc=d3e41499-112717 + Details
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- Definition Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121583591&loc=SL98516268-108586 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)(a)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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