Area of real estate property sublease additional office facilities.

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Commitments and contingencies.

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- Definition

Lessee operating sublease term of contract.

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- Definition

Potential upfront and milestone obligations and royalty obligations.

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- Definition

Area of a real estate property.

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- Definition

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

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-Publisher FASB
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- Definition

Indicates (true false) whether lessee has option to extend operating lease.

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- Definition

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

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Indicates (true false) whether sublessee has option to extend operating sublease.

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- Definition

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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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Indicates line item in statement of financial position that includes current operating lease liability.

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Indicates line item in statement of financial position that includes noncurrent operating 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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- Definition

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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Commitments and Contingencies (Details Textual) $ in Thousands, € in Millions		1 Months Ended		12 Months Ended
	Aug. 29, 2020 ft²	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Commitments And Contingencies [Line Items]
Area of office facilities taken on lease \| ft²	5,200
Operating lease term	42 months
Additional operating lease term	36 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
Area of additional office facilities taken on sublease \| ft²			3,000
Operating sublease term			29 months
Lessee, Operating Sublease, Existence of Option to Extend [true false]			false
Lessee, operating lease, assumptions and judgments, allocation of lease and nonlease component				The leases include 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					$ 84	$ 76
Lease liability				$ 483
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]				us-gaap:OtherLiabilitiesCurrent
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]				Operating lease liability, net of current portion
Weighted-average remaining lease term				4 years 8 months 12 days
Weighted-average discount rate				7.00%
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense				$ 109	$ 95
Research and development \| Patent Assignment Agreement \| University Medical Center of Johannes Gutenberg University Mainz
Commitments And Contingencies [Line Items]
Potential upfront and milestone obligations and royalty obligations \| €		€ 1.6