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Collaborative and Other Relationships - Summary of Activity Related to Sage Therapeutics (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2024
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |
Share of net profit from sage therapeutics, Percent | 50.00% |  | 50.00% |  |
Collaboration profit sharing/(loss reimbursement) | $ 62.4 | $ 56.9 | $ 128.0 | $ 114.0 |
Sage Therapeutics |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |
Collaboration profit sharing/(loss reimbursement) | 6.5 |  | 11.5 |  |
Sage Therapeutics | Forecast |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |
Potential future milestone payments commitment to third party |  |  |  |  | $ 75.0
Research and development | Sage Therapeutics |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |
Expense incurred by the collaboration | 9.6 | 52.1 | 21.2 | 86.9 |
Expense reflected within statements of income | 4.8 | 26.1 | 10.6 | 43.5 |
Selling, general and administrative | Sage Therapeutics |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |
Expense incurred by the collaboration | 26.9 | 60.1 | 54.5 | 98.3 |
Expense reflected within statements of income | $ 13.5 | $ 30.0 | $ 27.3 | $ 49.1 |

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