Liabilities Related to the Sales of Future Royalties - Schedule of Liability Related to Potential Future Royalties (Detail) - USD ($) $ in Thousands	12 Months Ended			36 Months Ended	142 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2023
Liability Related To Sale Of Future Royalties [Roll Forward]
Liabilities related to the sales of future royalties—beginning balance	$ 157,461				$ 0
Royalty monetization proceeds	0				274,000
Non-cash royalty revenue	(68,921)	$ (69,794)	$ (77,746)		(472,166)
Non-cash interest expense	25,334	28,911	$ 47,313		298,518
Payments to RPI	0				(10,000)
Loss on revaluation of liability related to the sale of future royalties	0				23,522
Liabilities related to the sales of future royalties – ending balance	113,874	157,461		$ 113,874	113,874
Less: unamortized transaction costs	(1,249)			(1,249)	(1,249)
Liabilities related to the sales of future royalties, net	112,625	155,378		112,625	112,625
2012 Purchase and Sale Agreement
Liability Related To Sale Of Future Royalties [Roll Forward]
Liabilities related to the sales of future royalties—beginning balance	55,167				0
Royalty monetization proceeds	0				124,000
Non-cash royalty revenue	(37,323)				(353,847)
Non-cash interest expense	6,373				240,542
Payments to RPI	0				(10,000)
Loss on revaluation of liability related to the sale of future royalties	0				23,522
Liabilities related to the sales of future royalties – ending balance	24,217	55,167		24,217	24,217
Less: unamortized transaction costs	0			0	0
Liabilities related to the sales of future royalties, net	24,217			24,217	24,217
2020 Purchase and Sale Agreement
Liability Related To Sale Of Future Royalties [Roll Forward]
Liabilities related to the sales of future royalties—beginning balance	102,294			0
Royalty monetization proceeds	0			150,000
Non-cash royalty revenue	(31,598)			(118,319)
Non-cash interest expense	18,961			57,976
Payments to RPI	0			0
Loss on revaluation of liability related to the sale of future royalties	0			0
Liabilities related to the sales of future royalties – ending balance	89,657	$ 102,294		89,657	89,657
Less: unamortized transaction costs	(1,249)			(1,249)	(1,249)
Liabilities related to the sales of future royalties, net	$ 88,408			$ 88,408	$ 88,408