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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) shares in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2025 USD ($) contract position shares | Jun. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) contract segment position shares | Jun. 30, 2024 USD ($) shares | Dec. 31, 2024 USD ($) | Jan. 31, 2010 cvr
Property, Plant and Equipment |  |  |  |  |  |
Number of operating segments | segment |  |  | 1 |  |  |
Number of reportable segments | segment |  |  | 1 |  |  |
Revenue recognized that was previously deferred | $ 300,000 | $ 500,000 | $ 600,000 | $ 1,000,000 |  |
Sale of Viking common stock (in shares) | shares | 0.0 |  | 0.0 | 0.7 |  |
Gain on sale of Viking common stock |  |  |  | $ 60,000,000 |  |
Number of positions in an unrealized loss position | position | 61 |  | 61 |  |  |
Unrealized losses | $ (60,000.00) |  | $ (60,000.00) |  |  |
Credit losses related to available-for-sale debt securities | 0 |  | 0 |  |  |
Amortized cost |  | 50,000.00 |  | 50,000.00 |  |
Increase (decrease) in allowance for credit losses | 100,000 | 200,000 | 400,000 | (100,000) |  |
Inventory write-down | 0 | 200,000 | 0 | 200,000 |  |
Inventory | 15,489,000 |  | 15,489,000 |  | $ 14,114,000 |
Fair value adjustments to partner program derivatives | (1,276,000) | 0 | (833,000) | 0 |  |
Gain on derivative instrument |  | 1,200,000 |  | 1,200,000 |  |
Losses from equity method investment in Primrose Bio |  |  | 0 | 10,382,000 |  |
Observable price changes | $ 0 | (25,800,000) | $ 0 | (25,800,000) |  |
Primrose mRNA |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Investment owned, net assets, percentage | 31.40% |  | 31.40% |  | 31.40% |
Losses from equity method investment in Primrose Bio |  | 2,200,000 |  | 4,600,000 |  |
Equity method investments |  |  |  |  | $ 0 |
Impairment of equity method investment | $ 0 | (5,800,000) | $ 0 | (5,800,000) |  |
Vikings |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Fair value adjustments to partner program derivatives |  | 15,200,000 |  | 15,200,000 |  |
Performance Shares |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Performance period for awards (in years) |  |  | 3 years |  |  |
Metabasis Therapeutics |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Number of contingent value rights issued | cvr |  |  |  |  |  | 4
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% |  |  |
Partner Programs |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Fair value adjustments to partner program derivatives | $ 1,200,000 |  | $ 600,000 |  |  |
Agenus Partnered Program |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Percentage of milestones (as a percent) | 50.00% |  | 50.00% |  |  |
Agenus Partnered Program | Primordial Genetics |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Number of contracts | contract | 2 |  | 2 |  |  |
Agenus, Inc. |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Fair value adjustments to partner program derivatives | $ 800,000 |  | $ (500,000) |  |  |
Gain on derivative instrument |  | 100,000 |  | 100,000 |  |
Primrose mRNA |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Fair value adjustments to partner program derivatives | (700,000) |  | (600,000) |  |  |
Gain on derivative instrument |  | $ 200,000 |  | $ 400,000 |  |
Castle Creek Investment |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Fair value adjustments to partner program derivatives | 300,000 |  | 300,000 |  |  |
Captisol |  |  |  |  |  |
Property, Plant and Equipment |  |  |  |  |  |
Inventory | $ 2,600,000 |  | $ 2,600,000 |  | $ 3,100,000 |

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