Asset Purchase Agreements - Additional Information (Detail) - AbbVie Asset Purchase Agreement [Member] $ in Millions	Nov. 20, 2020 USD ($)
Asset Purchase Agreements [Line Items]
Payment for asset purchase agreement	$ 95.0
Progeria Research Foundation (PRF) Collaboration Agreement [Member]
Asset Purchase Agreements [Line Items]
Proceeds from sale	$ 46.5

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

Name:	us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration