Subsequent Events (Details) - USD ($)	May 07, 2024	Mar. 31, 2024	Dec. 31, 2023
Subsequent Events
Finance royalty agreement, value		$ 68,310,000	$ 62,291,000
Subsequent Event | Agenus, Inc.
Subsequent Events
Finance royalty agreement, value	$ 75,000,000
Royalties right to receive (as a percent)	18.75%
Financial royalty commitment	$ 25,000,000
Maximum capital sourcing	125,000,000
Maximum financing royalty asset	$ 200,000,000
Securities called by warrants (in shares)	867,052
Exercise price (in USD per share)	$ 17.3
Subsequent Event | Agenus, Inc. | BMS-986442
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | AGEN2373
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | INCAGN2385
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | INCAGN2390
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | MK-4830
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | UGN-301
Subsequent Events
Future milestones right to receive (as a percent)	31.875%
Subsequent Event | Agenus, Inc. | BOT/BAL
Subsequent Events
Future royalties (as a percent)	2.625%