Organization and Business	3 Months Ended
Mar. 31, 2024
Accounting Policies [Abstract]
Organization and Business	1. Organization and Business Acadia Pharmaceuticals Inc. (the Company), based in San Diego, California, is a biopharmaceutical company focused on the development and commercialization of innovative medicines to address unmet medical needs in central nervous system (CNS) disorders and rare diseases. In April 2016, the U.S. Food and Drug Administration (FDA) approved the Company’s first drug, NUPLAZID® (pimavanserin), for the treatment of hallucinations and delusions associated with Parkinson’s disease psychosis (PDP). NUPLAZID became available for prescription in the United States in May 2016. In March 2023, the FDA approved the Company’s second drug, DAYBUE™ (trofinetide), for the treatment of Rett syndrome in adults and pediatric patients 2 years of age and older. DAYBUE became available for prescription in the United States in April 2023.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

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-Topic 205
-Name Accounting Standards Codification
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