Fair Value Measurements - Additional Information (Details) - BVF Partners L.P. - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
BVF Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Non-refundable payments received			$ 15	$ 15
Imputed effective rate of interest on unamortized portion of liability	10.10%	20.60%	20.60%
BVF Agreement | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent payments upon achievement of certain clinical and regulatory milestones				73
Gilead Collaboration Agreement | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent payments upon achievement of certain clinical and regulatory milestones				$ 160