Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Asset Purchase Agreement, Royalties As Percent Of Aggregated Net Sales

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Increase (Decrease) In Operating Lease, Right-Of-Use Asset

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Lessee, Operating Lease, Rent Holiday Period

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Operating And Variable Leases, Cost

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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands			1 Months Ended		3 Months Ended		9 Months Ended
	Aug. 01, 2022	Mar. 31, 2021	Mar. 31, 2021	May 31, 2016	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Apr. 07, 2020	Apr. 12, 2019
Loss Contingencies [Line Items]
Incremental borrowing rate on operating leases					6.00%		6.00%
Operating and variable lease costs					$ 232	$ 133	$ 498	$ 372
Contractual obligation					$ 2,700		$ 2,700
Asset purchase agreement, royalties as percent of aggregated net sales				4.40%
Common stock, shares issued (in shares)					30,564,995		30,564,995		26,335,418		120,070
Common stock issued					$ 3		$ 3		$ 3		$ 1,500
4SC Royalty Settlement (see Note 4)					$ 0	$ 0	$ 0	$ 17,250
Immunic AG
Loss Contingencies [Line Items]
Asset purchase agreement, royalties as percent of aggregated net sales		4.40%
4SC Royalty Settlement (see Note 4)		$ 17,250
Royalty settlement agreement, cash payment, percent		50.00%	50.00%
Royalty settlement agreement, shares payment, percent		50.00%	50.00%
Grafelfing, Germany
Loss Contingencies [Line Items]
Lease term (in years)										5 years
Additions to right-of-use assets	$ 642		$ 435
New York City
Loss Contingencies [Line Items]
Rent holiday period							6 months