Basis of Presentation and Summary of Significant Accounting Policies - Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue
Total revenues and income	$ 78,746	$ 115,461	$ 194,161	$ 208,421
Royalties
Disaggregation of Revenue
Total revenues and income	70,284	46,586	161,274	110,472
Revenue from intangible royalty assets
Disaggregation of Revenue
Total revenues and income	47,427	40,161	117,720	91,832
Filspari
Disaggregation of Revenue
Total revenues and income	16,839	9,078	41,728	20,957
Kyprolis
Disaggregation of Revenue
Total revenues and income	10,489	11,619	24,273	25,145
Capvaxive
Disaggregation of Revenue
Total revenues and income	3,801	3,206	8,086	6,341
Ohtuvayre
Disaggregation of Revenue
Total revenues and income	3,704	2,717	10,835	6,213
Rylaze
Disaggregation of Revenue
Total revenues and income	3,534	3,557	9,956	9,540
Teriparatide injection
Disaggregation of Revenue
Total revenues and income	1,325	2,632	4,116	6,121
Vaxneuvance
Disaggregation of Revenue
Total revenues and income	1,070	2,039	4,031	5,967
Other
Disaggregation of Revenue
Total revenues and income	6,665	5,313	14,695	11,548
Income from financial royalty assets
Disaggregation of Revenue
Total revenues and income	22,857	6,425	43,554	18,640
Ojemda
Disaggregation of Revenue
Total revenues and income	7,002	0	7,002	0
Qarziba
Disaggregation of Revenue
Total revenues and income	5,952	5,976	18,401	17,303
Vabysmo
Disaggregation of Revenue
Total revenues and income	3,578	0	3,578	0
Ohtuvayre inventors
Disaggregation of Revenue
Total revenues and income	3,251	0	9,592	0
Miplyffa
Disaggregation of Revenue
Total revenues and income	1,675	0	1,675	0
Other
Disaggregation of Revenue
Total revenues and income	1,399	449	3,306	1,337
Captisol
Disaggregation of Revenue
Total revenues and income	7,946	10,672	24,578	32,419
Income from Pelthos Transaction
Disaggregation of Revenue
Total revenues and income	0	53,072	0	53,072
Contract revenue and income
Disaggregation of Revenue
Total revenues and income	516	58,203	8,309	65,530
Contract revenue
Disaggregation of Revenue
Total revenues and income	341	131	3,134	6,441
Income
Disaggregation of Revenue
Total revenues and income	$ 175	$ 5,000	$ 5,175	$ 6,017