Significant Contracts - Additional Information (Detail)		1 Months Ended		3 Months Ended			6 Months Ended
	Oct. 26, 2015 USD ($)	Apr. 30, 2021 USD ($)	Oct. 31, 2019 License	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2022 USD ($) Option	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Jul. 01, 2021	Apr. 30, 2020 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Non-current deferred revenue				$ 12,323,000			$ 12,323,000		$ 12,323,000
Current deferred revenue									1,011,000
Research and development expense				123,223,000	$ 82,332,000		241,468,000	$ 153,971,000
General and Administrative Expense				26,273,000	28,806,000		54,294,000	52,303,000
Collaboration Expense				33,922,000	26,945,000		64,568,000	46,891,000
A&R JDCA [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Percentage of net profits and net losses		40.00%								40.00%
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Nonrefundable upfront payment received	$ 75,000,000.0
Non-current deferred revenue				12,300,000			12,300,000		12,300,000
Transaction price allocated to remaining performance obligations				12,300,000			12,300,000
Current deferred revenue				0			0		0
Maximum potential future payments							775,000,000.0
Revenue					900,200,000			900,400,000
Collaboration Expense				33,900,000	26,900,000		64,600,000	46,900,000
Collaboration Expense Reimbursements Received				9,100,000	$ 12,600,000		16,500,000	$ 23,200,000
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member] | Collaboration Target Options [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone payment receivable				420,000,000.0			420,000,000.0
Milestone payment receivable				410,000,000.0			410,000,000.0
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member] | Joint Development Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Up-front payment received							$ 7,000,000.0
Agreement description							In connection with the JDA, the Company received a $7.0 million up-front payment from Vertex and subsequently received a one-time low seven-digit milestone payment upon the dosing of the second patient in a clinical trial with the initial product candidate.
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member] | Exercise of Exclusive Option [Member] | Collaboration Target Options [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone payment receivable				10,000,000			$ 10,000,000
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member] | 2019 Collaboration Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Nonrefundable upfront payment received							175,000,000.0
Maximum potential payments				825,000,000.0			$ 825,000,000.0
Percentage of exchange payment of research and development costs							50.00%
Vertex Pharmaceuticals Incorporated and Certain of its Subsidiaries [Member] | 2015 Collaboration Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone payment receivable				395,000,000.0			$ 395,000,000.0
Percentage of exchange payment of research and development costs							50.00%
Number of options would not be exercised under agreement | Option							1
Number of remaining options under agreement | Option							4
Vertex Pharmaceuticals Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Maximum potential future payments							$ 200,000,000.0
Vertex Pharmaceuticals Inc [Member] | Exclusive License [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Estimated standalone selling price for single collaboration							900,000,000.0
Vertex Pharmaceuticals Inc [Member] | 2019 Collaboration Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone payment receivable									$ 12,500,000		$ 25,000,000.0
Remaining Milestone Payment Receivable				$ 775,000,000.0			775,000,000.0
Vertex Pharmaceuticals Inc [Member] | 2015 Collaboration Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate amount in option exercise payments received						$ 30,000,000.0
Number of exclusive license targets | License			3
Vertex Pharmaceuticals Inc [Member] | A&R JDCA [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Up-front payment received		$ 900,000,000.0					$ 900,000,000.0
Milestone payment receivable		$ 200,000,000.0
Percentage of net profits and net losses		60.00%								60.00%
Additional interest of percentage							10.00%