| Cover Page - shares | 3 Months Ended | |
| Mar. 31, 2021 | Apr. 23, 2021 | |
| Cover [Abstract] | ||
| Document Type | 10-Q/A | |
| Document Quarterly Report | true | |
| Document Period End Date | Mar. 31, 2021 | |
| Document Transition Report | false | |
| Entity File Number | 001-36014 | |
| Entity Registrant Name | AGIOS PHARMACEUTICALS, INC. | |
| Entity Incorporation, State or Country Code | DE | |
| Entity Tax Identification Number | 26-0662915 | |
| Entity Address, Address Line One | 88 Sidney Street | |
| Entity Address, City or Town | Cambridge | |
| Entity Address, State or Province | MA | |
| Entity Address, Postal Zip Code | 02139 | |
| City Area Code | 617 | |
| Local Phone Number | 649-8600 | |
| Title of 12(b) Security | Common Stock, Par Value $0.001 per share | |
| Trading Symbol | AGIO | |
| Security Exchange Name | NASDAQ | |
| Entity Current Reporting Status | Yes | |
| Entity Interactive Data Current | Yes | |
| Entity Filer Category | Large Accelerated Filer | |
| Entity Small Business | false | |
| Entity Emerging Growth Company | false | |
| Entity Shell Company | false | |
| Entity Common Stock, Shares Outstanding | 61,574,283 | |
| Document Fiscal Year Focus | 2021 | |
| Document Fiscal Period Focus | Q1 | |
| Amendment Flag | true | |
| Entity Central Index Key | 0001439222 | |
| Current Fiscal Year End Date | --12-31 | |
| Amendment Description | This Amendment No. 1 (the “Amendment”) to the Quarterly Report on Form 10-Q of Agios Pharmaceuticals, Inc. (the “Company”) for the quarter ended March 31, 2021, originally filed with the Securities and Exchange Commission on April 29, 2021 (the “Original Form 10-Q”), is being filed solely to correct the number of outstanding shares of the Company’s common stock, as of April 23, 2021, listed on the cover page to 61,574,283. This Amendment is limited in scope to the correction described above and does not amend, update, or change any other items or disclosures contained in the Original Form 10-Q. Accordingly, all other items that remain unaffected are omitted in this filing. Except as described in the preceding paragraph, this Amendment does not update any of the information contained in the Original Form 10-Q, which continues to speak as of the original filing date of the Original Form 10-Q. As required by Rule 12b-15 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), we are filing as exhibits to this Amendment the certifications required by Rule 13a-14(a) or Rule 15d-14(a) of the Exchange Act as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 by the Company’s principal executive officer and principal financial officer. The Company is omitting paragraphs 3, 4 and 5 of such certifications because no financial statements have been included in this Amendment and because this Amendment does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K. The Company is not including certifications pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 because no financial statements have been included in this Amendment. |
