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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) shares in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 31, 2010 cvr | Sep. 30, 2024 USD ($) position shares | Sep. 30, 2023 USD ($) shares | Sep. 30, 2024 USD ($) position segment shares | Sep. 30, 2023 USD ($) shares | Jun. 30, 2024 USD ($) | May 29, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 18, 2023 contract
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Number of reportable segments | segment |  |  |  | 1 |  |  |  |  |
Revenue recognized that was previously deferred |  | $ 200,000 | $ 0 | $ 1,200,000 | $ 0 |  |  |  |
Sale of Viking common stock (in shares) | shares |  | 0 | 0 | 700 | 4,500 |  |  |  |
Gain on sale of Viking common stock |  |  |  | $ 60,000,000 | $ 37,200,000 |  |  |  |
Number of positions in an unrealized loss position | position |  | 32 |  | 32 |  |  |  |  |
Unrealized losses |  | $ (10,000.00) |  | $ (10,000.00) |  |  |  |  |
Amortized cost |  |  |  | 50,000.00 |  |  |  |  |
Credit losses related to available-for-sale debt securities |  | 0 | $ 0 |  | 0 |  |  |  |
(Decrease) increase in allowance for credit losses |  | (10,000.00) | 100,000 | (130,000) | 140,000 |  |  |  |
Inventory write-down |  | 100,000 | 0 | 200,000 | 0 |  |  |  |
Inventory |  | 16,740,000 |  | 16,740,000 |  |  |  | $ 23,969,000 |
Fair value adjustments to partner program derivatives |  | $ (7,812,000) | 0 | $ (7,812,000) | 0 |  |  |  |
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Gain (Loss) on Investments |  | Gain (Loss) on Investments |  |  |  |  |
Received amount expended |  | $ 5,675,000 | $ 5,532,000 | $ 17,000,000 | $ 19,049,000 |  |  |  |
Employee retention credit |  | 2,300,000 |  | 2,300,000 |  |  |  |  |
Financial royalty liability current |  | 6,600,000 |  | 6,600,000 |  |  |  |  |
Prepaid expense |  | $ 2,200,000 |  | $ 2,200,000 |  |  |  |  |
Potentially dilutive shares excluded from calculation due to anti-dilutive effect (in shares) | shares |  | 1,099 | 4,762 | 1,815 | 4,663 |  |  |  |
Metabasis |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Number of CVRs issued per acquiree share | cvr | 4 |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Potentially dilutive shares excluded from calculation due to anti-dilutive effect (in shares) | shares |  | 700 | 300 |  |  |  |  |  |
Performance Shares |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Performance period for awards (in years) |  |  |  | 3 years |  |  |  |  |
Minimum | Performance Shares |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Payout range (as a percent) |  |  |  | 0.00% |  |  |  |  |
Maximum | Performance Shares |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Payout range (as a percent) |  |  |  | 200.00% |  |  |  |  |
Other Derivatives |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Fair value adjustments to partner program derivatives |  | $ (8,000,000) |  | $ (6,800,000) |  |  |  |  |
Agenus Partnered Program |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Additional maximum investment |  |  |  |  |  |  | $ 25,000,000 |  |
Percentage of milestones (as a percent) |  |  |  |  |  |  |  |  | 50.00%
Agenus Partnered Program | Primordial Genetics |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Number of contracts | contract |  |  |  |  |  |  |  |  | 2
Viking | Collars |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Fair value adjustments to partner program derivatives |  | (7,900,000) |  | 7,300,000 |  |  |  |  |
Agenus, Inc. | Partner Programs |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Fair value adjustments to partner program derivatives |  | (7,200,000) |  | (7,200,000) |  |  |  |  |
Primrose Bio |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Fair value adjustments to partner program derivatives |  | $ (600,000) | $ 0 | $ (600,000) | $ 0 |  |  |  |
Palvella |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Convertible note |  |  |  |  |  | $ 2,500,000 |  |  |
Convertible note maturity period (in years) |  |  |  |  |  | 3 years |  |  |
Palvella | Minimum |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Interest in sales revenue (as a percent) |  | 8.00% |  | 8.00% |  |  |  |  |
Palvella | Maximum |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Interest in sales revenue (as a percent) |  | 9.80% |  | 9.80% |  |  |  |  |
Palvella | Royalty Agreements |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Additional royalties receivable under sales-based milestones |  | $ 5,000,000 |  | $ 5,000,000 |  |  |  |  |
Received amount expended |  |  |  | 700,000 |  |  |  |  |
Captisol |  |  |  |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Inventory |  | $ 3,300,000 |  | $ 3,300,000 |  |  |  | $ 4,600,000 |

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