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Commitments and Contingencies (Details Textual) $ in Thousands		3 Months Ended
	Aug. 29, 2020 ft²	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Aug. 01, 2013 ft²
Commitments And Contingencies [Line Items]
Area of office facilities taken on lease | ft²	5,200			5,300
Operating lease term	42 months
Additional operating lease term	36 months
Weighted-average discount rate	7.00%	7.00%
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		$ 7	$ 25
Lease liability		$ 450
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]		Accrued expenses and other liabilities
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]		Operating lease liability, net of current portion
Weighted-average remaining lease term		6 years
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense		$ 22	$ 23

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Area of a real estate property.

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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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Indicates (true false) whether lessee has option to extend 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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Present value of lessee's discounted obligation for lease payments from operating lease.

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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 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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