Regeneron License and Collaboration Arrangement - Additional Information (Details) - USD ($)			6 Months Ended			12 Months Ended
	Jul. 31, 2019	Jul. 29, 2016	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2018	Dec. 31, 2017
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Licence agreement additional revenue recognised			$ 5,000.0
Licence agreement cumulative revenue recognised				$ 27,800,000
Regeneron Pharmaceuticals, Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Exercise Fee Paid			20,000,000.0
Contingent Consideration fees		$ 20,000,000.0
Option exercise fee			20,000,000.0
Contract Assets			0
Agreement transaction price		55,000,000.0
Licence agreement additional revenue recognised			25,000,000.0
Research funding fee		30,000,000.0
Non refundable upfront payment received			25,000,000.0
Additional payment for research funding received		30,000,000.0	$ 20,000,000.0			$ 5,000,000.0	$ 5,000,000.0
License agreement termination description			twelve (12) years
Upfront payment		$ 25,000,000.0		25,000,000.0
Licence agreement cumulative revenue recognised					$ 10,000,000.0
Increase in estimated transaction price	$ 35,000.0
Contract liability			$ 0	$ 13,100,000
Regeneron Pharmaceuticals, Inc. | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Licence agreement additional amount payable of option exercise fees			80,000,000.0
Increase in estimated transaction price			45,000,000.0
Regeneron Pharmaceuticals, Inc. | Minimum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Increase in estimated transaction price			$ 10,000,000.0