Stock-Based Compensation - Equity Incentive and Employee Stock Purchase Plans (Details) $ in Millions	9 Months Ended
Sep. 30, 2022 USD ($) shares
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining period over which unrecognized compensation expense will be recognized	2 years 4 months 24 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining period over which unrecognized compensation expense will be recognized	1 year
Stock-based compensation expense	$ 0.1
Assumed Aceragen Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of options granted	10 years
Unrecognized compensation expense	$ 4.7
Weighted average remaining period over which unrecognized compensation expense will be recognized	3 years 9 months
Forfeited \| shares	3,278,859
Assumed Aceragen Stock Incentive Plan \| Stock options \| Employee option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee option vesting percentage	25.00%
Vesting period	3 years
Assumed Aceragen Stock Incentive Plan \| Stock options \| Non-employee Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Assumed Aceragen Stock Incentive Plan \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining period over which unrecognized compensation expense will be recognized	2 years
Unrecognized compensation expense related to the restricted stock units	$ 0.7

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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