License and Collaboration Agreements - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 31, 2021
Series A-2 Convertible Preferred Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Share issue price					$ 4.00
Series B Convertible Preferred Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Convertible preferred stock shares issued				27,223
Share issue price	$ 16.00
Beam Therapeutics Inc. (Beam) | Research and Development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment to collaborators			$ 50,000,000.0
Beam Therapeutics Inc. (Beam) | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Developmental and commercial milestone payments and royalties on licensed products payable						$ 65,000,000.0
Beam Therapeutics Inc. (Beam) | Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Beneficial ownership percentage held by a member of board of directors						10.00%
Harvard College
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment to collaborators		$ 3,000,000.0
Share issue price		$ 4.00
Total consideration under license agreement		$ 12,000,000.0
Research and development expense					$ 12,000,000.0
Estimated fair value of contingent license payment					4,600,000
Research and development expense				$ 1,400,000	4,600,000
Maximum period expected to achieve for success payments		12 years
Estimated fair value of success payment liability			14,200,000	11,800,000
Harvard College | Short-term Liabilities
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Estimated fair value of success payment liability			5,000,000.0	0
Harvard College | Long-term Liabilities
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Estimated fair value of success payment liability			9,200,000	11,800,000
Harvard College | Series A-2 Convertible Preferred Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Convertible preferred stock shares issued		2,200
Share issue price		$ 4.00
Harvard College | Series B Convertible Preferred Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License payment upon closing of equity financing	$ 6,000,000.0
Harvard College | Research and Development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Expense in connection with change in estimated fair value of success payment liability			$ 2,400,000	$ 9,900,000	$ 1,900,000
Harvard College | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential success payment		$ 175,000,000.0