Related Party Transactions - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Related Party Transaction [Line Items]
Share of common stock held from Regeneron	24,956,556		24,951,983
Unbilled accounts receivable due from Regeneron	$ 10,000,000.0		$ 11,400,000
Amount due to Regeneron	0		0
Contra-research and development expense	3,000,000.0	$ 1,900,000
Consulting services expenses	0	$ 200,000
Due to related party	$ 0		$ 100,000
Regeneron Agreement
Related Party Transaction [Line Items]
Share of common stock held from Regeneron	2,097,314

Carrying amount as of the balance sheet date of obligations due all related parties.

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+ Details