Investments and Other Assets - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Reclassification of other comprehensive loss - equity method investment	$ 2,132,000
Investments and other assets	70,957,000		$ 42,883,000
Change in fair value of investments, net	(6,065,000)	$ 0
Collaboration revenue	28,935,000	12,606,000
Accrued expenses	43,276,000		67,017,000
AvenCell Therapeutics, Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Reclassification of other comprehensive loss - equity method investment	2,100,000
Investments and other assets	9,600,000
Kyverna Therapeutics Inc [Member]
Schedule of Equity Method Investments [Line Items]
Investment Owned, Balance, Principal Amount	29,200,000
Change in fair value of investments, net	19,200,000
Investment Owned, Fair Value			10,000,000
AvenCell [Member]
Schedule of Equity Method Investments [Line Items]
Change in fair value of investments, net	25,300,000
Investment Owned, Fair Value			$ 11,800,000
Collaboration revenue	21,000,000	4,900,000
Accounts receivable	200,000
Accrued expenses	$ 1,000,000
AvenCell [Member] | AvenCell Therapeutics, Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	33.33%		33.33%
Collaboration revenue	$ 0
Sparing Vision [Member]
Schedule of Equity Method Investments [Line Items]
Investment Owned, Fair Value	14,600,000
Collaboration revenue	$ 500,000	$ 400,000