Area of real estate property sublease additional office facilities.

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Commitments and contingencies.

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Lessee operating sublease term of contract.

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Potential upfront and milestone obligations and royalty obligations.

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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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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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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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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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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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The number of positions eliminated during the period as a result of restructuring activities.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Commitments and Contingencies (Details Textual) $ in Thousands, € in Millions		1 Months Ended			9 Months Ended
	Aug. 29, 2020 ft²	Jul. 31, 2022 USD ($) Employee	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Commitments And Contingencies [Line Items]
Workforce reduction, percentage		67.00%
Workforce reduction, number of employees \| Employee		12
Area of office facilities taken on lease \| ft²	5,200
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
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					$ 98	$ 52
Lease liability					$ 409
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]					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					4 years 1 month 6 days
One-time Termination Benefits
Commitments And Contingencies [Line Items]
Restructuring charges		$ 790
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense					$ 94	$ 78
General and Administrative Expense \| One-time Termination Benefits
Commitments And Contingencies [Line Items]
Restructuring charges		300
Accrued Compensation And Employee Benefits
Commitments And Contingencies [Line Items]
Restructuring charges					$ 250
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
Research and development \| One-time Termination Benefits
Commitments And Contingencies [Line Items]
Restructuring charges		$ 490