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Commitments and Contingencies (Details Textual) $ in Thousands			12 Months Ended
	Oct. 10, 2019 USD ($)	Mar. 02, 2016	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Aug. 01, 2013 ft²
Commitments And Contingencies [Line Items]
Area of office facilities taken on lease | ft²					5,300
Additional operating lease term	4 months	38 months
Lease renewal start date	Dec. 01, 2019	Oct. 01, 2016
Lease expiration date	Mar. 31, 2020	Nov. 30, 2019
Future undiscounted minimum lease payments	$ 34
Lease renewal option			Under the October 2019 Amendment, the Company has no further rights to extend or renew this lease agreement.
Lessee, Operating Lease, Existence of Option to Extend [true false]			false
Future minimum lease payments			$ 25
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.
Lease liability			$ 25
Operating lease, liability, current, statement of financial position [Extensible List]			us-gaap:OtherAccruedLiabilitiesCurrent
Operating lease, cash paid for measurement of lease liabilities			$ 91
Weighted-average remaining lease term			2 months 12 days
Weighted-average discount rate			7.50%
Royalty buy down due period			6 months
Minimum
Commitments And Contingencies [Line Items]
Percentage of royalty obligation			12.50%
Percentage of range of royalties that can be bought down			12.50%
Maximum
Commitments And Contingencies [Line Items]
Percentage of royalty obligation			25.00%
Percentage of range of royalties that can be bought down			17.00%
Upon Food and Drug Administration Approval
Commitments And Contingencies [Line Items]
Expected milestone payments due upon approval			$ 8,000
Upon Regulatory Marketing Approval
Commitments And Contingencies [Line Items]
Expected milestone payments due upon approval			$ 5,000
CPEC
Commitments And Contingencies [Line Items]
Percentage of royalty obligation			5.00%
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense			$ 74
Rent expense				$ 82
Westminster, Colorado
Commitments And Contingencies [Line Items]
Future minimum lease payments				$ 83

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