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

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

+ References

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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- Definition

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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- Definition

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.

+ References

No definition available.

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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.

+ References

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- Definition

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.

+ References

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- Definition

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

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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- Definition

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

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

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

+ References

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

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- Definition

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

+ References

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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.

+ Details

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

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.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Granted, Weighted Average Exercise Price		$ 8.34	$ 45.56
Outstanding, Intrinsic Value		$ 102
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Accelerated vesting, number of shares	90,328
Unrecognized compensation cost related to nonvested stock-based compensation		$ 3,900
Weighted average remaining period over which unrecognized compensation expense will be recognized		2 years 8 months 12 days
Common Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Beginning Balance		305,838
Granted		68,796
Assumed in connection with Aceragen Acquisition		111,038
Forfeited		(15,963)
Expired		(63,535)
Options, Outstanding, Ending Balance		406,174	305,838
Exercisable, Ending Balance		239,866
Weighted Average Exercise Price, Beginning Balance		$ 137.08
Granted, Weighted Average Exercise Price		8.34
Assumed in connection with Aceragen Acquisition, Weighted Average Exercise Price		6.22
Forfeited, Weighted Average Exercise Price		3.27
Expired, Weighted Average Exercise Price		148.30
Weighted Average Exercise Price, Ending Balance		83.00	$ 137.08
Exercisable, Weighted Average Exercise Price		$ 132.26
Outstanding, Weighted Average Remaining Contractual Term		6 years 1 month 6 days	5 years 10 months 24 days
Exercisable, Weighted Average Remaining Contractual Term		4 years 1 month 6 days
Exercisable, Intrinsic Value		$ 54
Preferred Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Assumed in connection with Aceragen Acquisition		19,826
Forfeited		(2,304)
Options, Outstanding, Ending Balance		17,522
Exercisable, Ending Balance		5,229
Assumed in connection with Aceragen Acquisition, Weighted Average Exercise Price		$ 365.96
Forfeited, Weighted Average Exercise Price		130.00
Weighted Average Exercise Price, Ending Balance		397.02
Exercisable, Weighted Average Exercise Price		$ 317.43
Outstanding, Weighted Average Remaining Contractual Term		9 years 1 month 6 days
Exercisable, Weighted Average Remaining Contractual Term		8 years 10 months 24 days
Outstanding, Intrinsic Value		$ 1,073
Exercisable, Intrinsic Value		$ 568