Collaborative and Other Relationships - Summary of Activity Related to Sage Therapeutics (Details) - Sage Therapeutics - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Research and Development Expense [Member]
Collaborative arrangements and non-collaborative arrangement transactions
Expense incurred by the collaboration	$ 1.2	$ 2.4
Expense reflected within statements of income	0.6	1.2
Selling, General and Administrative Expenses [Member]
Collaborative arrangements and non-collaborative arrangement transactions
Expense incurred by the collaboration	47.5	43.5
Expense reflected within statements of income	$ 23.7	$ 21.7