Basis of Presentation and Summary of Significant Accounting Policies - Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue
Total revenues and income	$ 63,693	$ 47,627	$ 115,415	$ 92,960
Royalties
Disaggregation of Revenue
Total revenues and income	48,032	36,397	90,990	63,886
Revenue from intangible royalty assets
Disaggregation of Revenue
Total revenues and income	37,362	30,084	70,293	51,671
Filspari
Disaggregation of Revenue
Total revenues and income	13,567	6,578	24,889	11,879
Kyprolis
Disaggregation of Revenue
Total revenues and income	7,044	8,803	13,784	13,526
Ohtuvayre
Disaggregation of Revenue
Total revenues and income	4,144	2,084	7,131	3,496
Rylaze
Disaggregation of Revenue
Total revenues and income	3,201	2,864	6,422	5,983
Capvaxive
Disaggregation of Revenue
Total revenues and income	2,316	2,250	4,285	3,135
Vaxneuvance
Disaggregation of Revenue
Total revenues and income	1,351	2,643	2,961	3,928
Teriparatide injection
Disaggregation of Revenue
Total revenues and income	1,470	2,298	2,791	3,489
Other
Disaggregation of Revenue
Total revenues and income	4,269	2,564	8,030	6,235
Income from financial royalty assets
Disaggregation of Revenue
Total revenues and income	10,670	6,313	20,697	12,215
Qarziba
Disaggregation of Revenue
Total revenues and income	6,150	5,885	12,449	11,327
Ohtuvayre inventors
Disaggregation of Revenue
Total revenues and income	3,294	0	6,341	0
Other
Disaggregation of Revenue
Total revenues and income	1,226	428	1,907	888
Captisol
Disaggregation of Revenue
Total revenues and income	7,978	8,287	16,632	21,747
Contract revenue and income
Disaggregation of Revenue
Total revenues and income	7,683	2,943	7,793	7,327
Contract revenue
Disaggregation of Revenue
Total revenues and income	2,683	1,926	2,793	6,310
Income
Disaggregation of Revenue
Total revenues and income	$ 5,000	$ 1,017	$ 5,000	$ 1,017