Represents annual accelerate percentage of options vested during the period.

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Amount of share-based compensation arrangement by share-based payment award, options, option Assumed in connection.

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Share-based compensation arrangement by share-based payment award, options, options assumed in connection, weighted average remaining contractual term.

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No definition available.

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Represents annual accelerate percentage of options vested every year.

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No definition available.

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- Definition

Share-based compensation arrangements by share-based payment award, options, option assumed in connection, weighted average exercise price

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No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, 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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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Publisher FASB
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

+ References

No definition available.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Granted, Weighted Average Exercise Price		$ 0.49	$ 2.68
Share based compensation arrangement by share based payment award options, annual accelerate percentage of options vested		6.25%
Share based compensation arrangement by share based payment award options, percentage of options vested every year		25.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Accelerated vesting, number of shares	1,535,578
Unrecognized compensation cost related to nonvested stock-based compensation		$ 1,000
Weighted average remaining period over which unrecognized compensation expense will be recognized		2 years 4 months 24 days
Common Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Beginning Balance		5,202,006
Granted		1,169,800
Expired		(588,038)
Options assumed in connection with Aceragen Acquisition		1,887,860
Options, Outstanding, Ending Balance		7,671,628		5,202,006
Exercisable, Ending Balance		4,218,823
Weighted Average Exercise Price, Beginning Balance		$ 8.06
Granted, Weighted Average Exercise Price		0.49
Expired, Weighted Average Exercise Price		2.87
Options assumed in connection with Aceragen Acquisition, Weighted Average Exercise Price		4.15
Weighted Average Exercise Price, Ending Balance		6.34		$ 8.06
Exercisable, Weighted Average Exercise Price		$ 9.29
Options assumed in connection with Aceragen acquisition, Weighted Average Remaining Contractual Term		9 years 3 months 18 days
Outstanding, Ending balance, Weighted Average Remaining Contractual Term		7 years 3 months 18 days		5 years 10 months 24 days
Exercisable Ending Balance, Weighted Average Remaining Contractual Term		5 years 8 months 12 days
Outstanding, Intrinsic Value, Ending Balance				$ 2,949
Preferred Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Options assumed in connection with Aceragen Acquisition		19,826
Options, Outstanding, Ending Balance		19,826
Exercisable, Ending Balance		2,187
Options assumed in connection with Aceragen Acquisition, Weighted Average Exercise Price		$ 394.82
Weighted Average Exercise Price, Ending Balance		394.82
Exercisable, Weighted Average Exercise Price		$ 142.05
Options assumed in connection with Aceragen acquisition, Weighted Average Remaining Contractual Term		9 years 3 months 18 days
Outstanding, Ending balance, Weighted Average Remaining Contractual Term		9 years 3 months 18 days
Exercisable Ending Balance, Weighted Average Remaining Contractual Term		8 years 10 months 24 days