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Commitments and Contingencies (Details Textual) $ in Thousands |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 29, 2020 ft² | Feb. 24, 2020 | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Aug. 01, 2013 ft²
Commitments And Contingencies [Line Items] |  |  |  |  |
Area of office facilities taken on lease | ft² | 5,200 |  |  |  | 5,300
Additional operating lease term | 36 months | 6 months |  |  |
Lease renewal start date |  | Apr. 01, 2020 |  |  |
Lease expiration date |  | Sep. 30, 2020 |  |  |
Operating lease term | 42 months |  |  |  |
Lease renewal option | option to renew for an additional 36 month term at the then prevailing rental rate. |  |  |  |
Lessee, Operating Lease, Existence of Option to Extend [true false] | true |  |  |  |
Lessee, operating lease, assumptions and judgments, allocation of lease and nonlease component |  |  | The lease includes real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation. |  |
Operating lease, cash paid for measurement of lease liabilities |  |  | $ 76 | $ 91 |
Lease liability |  |  | $ 450 |  |
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] |  |  | us-gaap:OtherAccruedLiabilitiesCurrent |  |
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] |  |  | us-gaap:OperatingLeaseLiabilityNoncurrent |  |
Weighted-average remaining lease term |  |  | 6 years 2 months 12 days |  |
Weighted-average discount rate |  |  | 7.00% |  |
General and Administrative Expense |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |
Rent expense |  |  | $ 95 | $ 74 |

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- Definition Description of assumptions and judgments used by lessee for allocating contract between lease and nonlease components for operating lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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