| Document and Entity Information | Dec. 31, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 31, 2020 |
| Entity Registrant Name | Acorda Therapeutics, Inc. |
| Entity Central Index Key | 0001008848 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-31938 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 13-3831168 |
| Entity Address, Address Line One | 420 Saw Mill River Road |
| Entity Address, City or Town | Ardsley |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10502 |
| City Area Code | (914) |
| Local Phone Number | 347-4300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of each class | Common Stock (Par Value $0.001) |
| Trading Symbol | ACOR |
| Name of each exchange on which registered | NASDAQ |
