Significant Agreements - Additional Information (Details)		1 Months Ended			3 Months Ended	12 Months Ended
	Oct. 24, 2023	Dec. 31, 2021 USD ($)	May 31, 2021 USD ($) Agreements	Jan. 31, 2020 USD ($) shares	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Shares issued | shares						349,321
Gilead Sciences, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration, option and license agreement, description					Pursuant to the Gilead Agreement, the Company also granted Gilead, on a research program-by-program basis, an exclusive option, exercisable at any time during the Option Period for such program, to obtain an exclusive license under such program’s intellectual property to develop, manufacture, and commercialize optioned products belonging to such program for a specified fee and on the terms and conditions set out in the Gilead Agreement. For purposes of the foregoing, an Option Period meant, on a program-by-program basis, the period commencing on the date of execution of the Gilead Agreement and ending upon the earlier of (i) the expiration of the review period for such program, and (ii) the ten-year anniversary of the date of execution of the Gilead Agreement.Unless terminated earlier, the Gilead Agreement was to expire, with respect to each program, (i) upon such program becoming a terminated program, or (ii) on an optioned product-by-optioned product and country-by-country basis, upon the expiration of the royalty term with respect to such optioned product in such country with respect to such program. Gilead had the right to terminate the Gilead Agreement at will, in its sole discretion, in its entirety or on a program-by-program or optioned program-by-optioned program basis at any time upon ninety days’ prior written notice to the Company. In addition, either party was able to terminate the Gilead Agreement for uncured material breach by the other party, or upon the occurrence of insolvency-related events of the other party.The royalty term under the Gilead Agreement continued on an optioned product-by-optioned product and country-by-country basis until the latest of: (i) the date on which there is no valid claim of a program patent; (ii) the expiration of any regulatory exclusivity with respect to such optioned product in the relevant country; and (iii) the ten-year anniversary of the date of the first commercial sale of such optioned product in such country.
Patent License Agreements | National Institutes of Health
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Minimum annual royalty payments			$ 200,000
Number of agreements | Agreements			2
Acquired licenses, amount paid			$ 3,300,000
Royalties payable					$ 0	$ 0
Patent License Agreements | Research and Development Expense | National Institutes of Health
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Acquired licenses, amount paid							$ 3,300,000
Patent License Agreements | Autologous Patent License Agreement | National Institutes of Health
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cumulative royalty due			5,700,000
Patent License Agreements | Allogeneic Patent License Agreement | National Institutes of Health
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cumulative royalty due			$ 1,700,000
License and Collaboration Agreement | Intellia Therapeutics, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Temporary equity shares issued, fair value		$ 7,000,000
Milestone payments					0	0
License and Collaboration Agreement | Intellia Therapeutics, Inc. | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments		$ 64,500,000
Collaboration, Option and License Agreement | Gilead Sciences, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from one-time non-refundable and non-creditable payment				$ 17,500,000
Estimated transaction price				17,500,000
Number of days of notice period for terminating agreement	90 days
Kite License Agreement | Kite Pharma, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sublicensing fee				6,300,000
License consideration								$ 3,500,000
Sublicense fee to be offset against future milestone payable, not agreed					3,800,000
Sublicense fee payable related to qualified financing						2,500,000
Kite License Agreement | Kite Pharma, Inc. | Accrued License Expense, Related Party
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sublicensing fee					$ 6,300,000	$ 6,300,000
Kite License Agreement | Kite Pharma, Inc. | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments				$ 10,800,000
Kite License Agreement | Kite Pharma, Inc. | Series A-2 Redeemable Convertible Preferred Stock
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Shares issued | shares				4,042,066
Kite License Agreement | Research and Development Expense | Kite Pharma, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sublicensing fee								$ 6,300,000
Stock Purchase Agreement | Gilead Sciences, Inc. | Series A-2 Redeemable Convertible Preferred Stock
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Shares issued | shares				6,890,744