Commitments and contingencies.

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Expected license agreement milestone payments.

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Lease renewal start date.

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License Agreement Percentage of Right to Buy Down Royalties

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License agreement percentage of royalty obligation.

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Royalty buy down due period.

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Area of a real estate property.

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Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

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Description of assumptions and judgments used by lessee for allocating contract between lease and nonlease components for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Commitments and Contingencies (Details Textual) $ in Thousands		3 Months Ended
	Mar. 02, 2016	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	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	38 months
Lease renewal start date	Oct. 01, 2016
Lease expiration date	Nov. 30, 2019
Lease renewal option	36-month
Future minimum lease payments		$ 60
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		$ 23
Weighted-average remaining lease term		8 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		$ 17
Rent expense			$ 21
Westminster, Colorado
Commitments And Contingencies [Line Items]
Future minimum lease payments				$ 83