Collaboration, Licensing and Other Arrangements - Summary of UT Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from UT	$ 51,253	$ 32,825	$ 140,490	$ 63,711
United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from UT	33,289	16,529	86,546	24,268
United Therapeutics Corporation | Commercial Supply Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from UT	12,800	9,916	34,897	15,795
United Therapeutics Corporation | License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from UT	271	393	698	1,949
United Therapeutics Corporation | Royalties Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from UT	$ 20,218	$ 6,220	$ 50,951	$ 6,524