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Represents the renewal term of the agreement.

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Development milestone obligations.

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Expert consultant fees and pass through costs.

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Incentive-based regulatory milestone fees.

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License maintenance fee annual.

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Milestone obligations.

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Milestone payments.

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No definition available.

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Non-refundable issue fee.

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Product agreement termination notice period.

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Product development fees.

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Royalties expiration description.

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Upfront cash payments.

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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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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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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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License, Collaboration, and Product Development Agreements - Additional Information (Detail) - USD ($) $ in Thousands				1 Months Ended			3 Months Ended	12 Months Ended
	Aug. 11, 2018	May 15, 2018	Apr. 20, 2016	Mar. 15, 2018	May 31, 2015	Sep. 30, 2010	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development									$ 64,436	$ 41,590	$ 51,791
Weighted-average period for recognition (in years)									2 years 8 months 12 days
Aggregate fair value of shares issued									$ 35	$ 34
Common stock, shares issued									34,568,821	33,878,486
Common Stock [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Sale of common stock									565,938	9,267,760	5,175,000
UPenn/CHOP Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Non-Refundable Issue Fee											$ 1,000
Milestone payment obligations									$ 0
UPenn/CHOP Agreement [Member] \| Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License maintenance fee									2,500
UPenn/CHOP Agreement [Member] \| Commercial Sales [Member] \| Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment obligations									18,000
Product Development Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Product development fees	$ 10,000
Expert consultant fees and pass through costs	800
Incentive-based regulatory milestone fees	$ 1,000
Number of common stock issued subject to quarterly vesting requirements	115,526
Product agreement termination notice period	90 days
Research and development									$ 200	$ 200	$ 200
Weighted-average period for recognition (in years)									3 months 18 days
Progeria Research Foundation (PRF) Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development				$ 2,000
Collaboration agreement initial term		10 years
Collaboration agreement subsequent renewal terms		2 years
BMS Transaction [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment			$ 2,000
BMS Transaction [Member] \| Common Stock [Member] \| BMS Purchase Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Sale of common stock			157,587
Aggregate fair value of shares issued			$ 3,200
BMS Transaction [Member] \| Commercial Sales [Member] \| Maximum [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment obligations			128,000
BMS Transaction [Member] \| Development and Regulatory Milestones [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment obligations			$ 61,000
BMS Transaction [Member] \| Development Phase 2 [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment obligations										$ 3,000
BMS Transaction [Member] \| Development Phase 3 [Member] \| Licensing Agreements [Member] \| Subsequent Event [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment obligations							$ 5,000
Merck Transaction [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate fair value of shares issued						$ 500
Common stock, shares issued						27,350
Milestone payments					$ 1,000				$ 0
Royalties expiration description										The Company is obligated to pay Merck up to an aggregate of $27.0 million in development milestones and will be required to pay tiered royalties based on aggregate annual net sales of all licensed products ranging from mid-single to low double-digit royalties on net sales.
Merck Transaction [Member] \| Licensing Agreements [Member] \| Subsequent Event [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payments								$ 1,000
Merck Transaction [Member] \| Development [Member] \| Maximum [Member] \| Licensing Agreements [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development milestone payment obligations						$ 27,000