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Summary of Significant Accounting Policies - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) ReportableUnit Segment | Dec. 31, 2018 USD ($) Segment
Summary Of Significant Accounting Policies [Line Items] |  |
Cash equivalents investments with original maturities | $ 0 | $ 0
Impairment loss | 0 | 0
Impairment charges | $ 0 |
Number of reporting units | ReportableUnit | 1 |
Qualifying expenditures related to research | $ 1,500,000 | 2,700,000
Interest or penalties related to income tax matters | $ 0 | $ 0
Number of operating segment | Segment | 1 | 1
Operating lease right-use-of assets | $ 781,000 |
Operating lease, liability | 793,000 |
BARDA Contract [Member] | Development [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Revenue recognized | $ 7,000,000 | $ 3,000,000
Customer Concentration Risk [Member] | Revenue Recognized [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Concentration risk percentage | 100.00% |
Customer Concentration Risk [Member] | Accounts Receivable [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Concentration risk percentage | 100.00% | 100.00%
Minimum [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Useful lives of the assets | 3 years |
Maximum [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Useful lives of the assets | 5 years |
Letter of Credit [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Letters of credit amount pursuant to lease agreement | $ 40,000 | $ 40,000

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- Definition This represents contract with BARDA to develop a new countermeasure for thermal burns entitling the company to be reimbursed for qualifying expenditures. + References No definition available. + Details
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