Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Collaborative and Other Relationships - Supernus Pharmaceuticals, Inc. (previously Sage Therapeutics, Inc.) and Denali Therapeutics Inc. (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Sage Therapeutics
Collaborative arrangements and non-collaborative arrangement transactions
Research and development expense				$ 75.0
Global licensing collaboration, development and commercial milestone payments	$ 700.0
Expected profit share percentage					50.00%
Collaboration profit (loss) sharing					$ 71.0	$ 27.0	$ 4.7
Share of net profit from sage therapeutics, percent				50.00%		50.00%	50.00%
Denali Therapeutics
Collaborative arrangements and non-collaborative arrangement transactions
Global licensing collaboration, development and commercial milestone payments		$ 1,100.0
Samsung Bioepis
Collaborative arrangements and non-collaborative arrangement transactions
Expected profit share percentage			45.00%		50.00%