Related Party Transactions (Details) - USD ($)			1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 16, 2021	Dec. 08, 2017	Jan. 31, 2024	Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Total current and non-current financial royalty assets, net				$ 14,125,889,000			$ 14,827,093,000
Upfront payment for financial royalty assets				86,084,000	$ 601,705,000
Shareholders' equity				9,863,716,000	9,822,000,000		10,084,289,000	$ 9,525,373,000
Treasury Stock
Related Party Transaction [Line Items]
Shareholders' equity				(2,654,000)	(2,828,000)		(2,629,000)	(2,806,000)
Non-Controlling Interests
Related Party Transaction [Line Items]
Shareholders' equity				3,363,965,000	3,868,251,000		3,557,792,000	$ 3,897,223,000
Related Party | Bristol-Myers Squibb
Related Party Transaction [Line Items]
Total current and non-current financial royalty assets, net				$ 68,300,000			75,600,000
Related Party | Errol De Souza
Related Party Transaction [Line Items]
Upfront payment for financial royalty assets			$ 2,500,000
Maximum milestone payment received			$ 2,220,000
Operating and Personnel Payments | Related Party
Related Party Transaction [Line Items]
Quarterly payments to affiliates, percent of adjusted cash receipts (as percent)				6.50%
Quarterly payments to affiliates, percent of security investment (as percent)				0.25%
Amount calculated for operating and personal payment				$ 1,000,000
Percent calculated for operating and personal payment				0.3125%
Operating and personnel payments incurred				$ 48,300,000
Former Operating and Personnel Payments | Related Party
Related Party Transaction [Line Items]
Operating and personnel payments incurred					$ 75,000,000
Assignment Agreement - Benefit of Payment Stream | Bristol-Myers Squibb
Related Party Transaction [Line Items]
Related party, rate (as percent)		50.00%
Assignment Agreement - Funding Obligations | Bristol-Myers Squibb
Related Party Transaction [Line Items]
Related party, rate (as percent)		50.00%
Agreement with MSCI
Related Party Transaction [Line Items]
Initial term (in years)	7 years
Amounts of transaction, related parties				$ 0		$ 0
Acquisition Of Limited Partnership Interests In Affiliate | Related Party
Related Party Transaction [Line Items]
Number of limited partnership interest acquired (in shares)				27,210
Acquisition Of Limited Partnership Interests In Affiliate | Related Party | Treasury Stock
Related Party Transaction [Line Items]
Shareholders' equity				$ 4,300,000
Acquisition Of Limited Partnership Interests In Affiliate | Related Party | Non-Controlling Interests
Related Party Transaction [Line Items]
Shareholders' equity				$ 1,600,000			$ 1,600,000