Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Assets	$ 26,795	$ 32,545
Total Liabilities	24,150
Warrant liability
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Liabilities	3,750
Issuance in connection with Acqusition of Aceragen, Inc.	3,866
Series X preferred stock liability
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Liabilities	20,400
Cash
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Cash equivalents - money market funds	4,680	250
Money market funds
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Cash equivalents - money market funds	22,115	32,295
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Assets	26,795	32,545
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) \| Cash
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Cash equivalents - money market funds	4,680	250
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) \| Money market funds
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Cash equivalents - money market funds	22,115	$ 32,295
Significant Unobservable Inputs (Level 3)
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Liabilities	24,150
Significant Unobservable Inputs (Level 3) \| Warrant liability
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Liabilities	3,750
Significant Unobservable Inputs (Level 3) \| Series X preferred stock liability
Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis
Total Liabilities	$ 20,400

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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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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Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Fair value of financial and nonfinancial obligations.

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