| Document and Entity Information - USD ($) | 12 Months Ended | ||
| Dec. 31, 2021 | Apr. 29, 2022 | Jun. 30, 2021 | |
| Cover [Abstract] | |||
| Document Type | 10-K/A | ||
| Amendment Flag | true | ||
| Amendment Description | EXPLANATORY NOTE This Amendment No. 1 on Form 10-K/A (this “Amendment”) is being filed by Allscripts Healthcare Solutions, Inc. (the "Company") to amend the Annual Report on Form 10-K for the year ended December 31, 2021 filed by the Company with the Securities and Exchange Commission (the "SEC") on February 25, 2022 (the “Original Report”). The sole purpose of this Amendment is to include the information required to be disclosed by Items 10 through 14 of Part III of Form 10-K. This information was previously omitted from the Original Report in reliance on General Instruction G(3) to Form 10-K, which permits the information to be incorporated in the Form 10-K by reference from a definitive proxy statement if the definitive proxy statement is filed no later than 120 days after the Company’s fiscal year-end. The Company is filing this Amendment solely to provide the information required by Part III of Form 10-K because the Company’s definitive proxy statement containing this information will not be filed until a later date.This Amendment amends and restates in their entirety the cover page and Items 10 through 14 of Part III of the Original Filing. In addition, pursuant to the rules of the SEC, the Company has also included as exhibits currently dated certifications required by Section 302 of the Sarbanes-Oxley Act of 2002. As such, this Amendment also amends and restates Item (a)(3) of the Exhibit Index of the Original Filing. Because no financial statements have been included in this Amendment and this Amendment does not contain or amend any disclosure with respect to Item 307 or Item 308 of Regulation S-K, paragraphs 3, 4 and 5 of the certifications required by Section 302 have been omitted, and the certifications required by Section 906 of the Sarbanes-Oxley Act of 2002 have been omitted. Except as otherwise expressly noted above, this Amendment does not amend any other information set forth in the Original Report. This Amendment continues to speak as of the date of the Original Report and, except where expressly noted, the Company has not updated disclosures contained herein or therein to reflect any events that occurred at a date subsequent to the date of the Original Report. Accordingly, this Amendment should be read in conjunction with the Original Report and the Company’s other filings with the SEC. | ||
| Document Period End Date | Dec. 31, 2021 | ||
| Document Fiscal Year Focus | 2021 | ||
| Document Fiscal Period Focus | FY | ||
| Document Annual Report | true | ||
| Document Transition Report | false | ||
| Entity File Number | 001-35547 | ||
| Entity Incorporation, State or Country Code | DE | ||
| Trading Symbol | MDRX | ||
| Entity Registrant Name | ALLSCRIPTS HEALTHCARE SOLUTIONS, INC. | ||
| Entity Tax Identification Number | 36-4392754 | ||
| Entity Central Index Key | 0001124804 | ||
| Entity Address, Address Line One | 222 Merchandise Mart Plaza | ||
| Entity Address, Address Line Two | Suite 2024 | ||
| Entity Address, City or Town | Chicago | ||
| Entity Address, State or Province | IL | ||
| Entity Address, Postal Zip Code | 60654 | ||
| City Area Code | 800 | ||
| Local Phone Number | 334-8534 | ||
| Title of 12(b) Security | Common Stock, par value $0.01 per share | ||
| Security Exchange Name | NASDAQ | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Well-known Seasoned Issuer | Yes | ||
| Entity Current Reporting Status | Yes | ||
| Entity Voluntary Filers | No | ||
| Entity Interactive Data Current | Yes | ||
| Entity Filer Category | Large Accelerated Filer | ||
| ICFR Auditor Attestation Flag | true | ||
| Entity Shell Company | false | ||
| Entity Small Business | false | ||
| Entity Emerging Growth Company | false | ||
| Entity Common Stock, Shares Outstanding | 115,536,855 | ||
| Entity Public Float | $ 2,251,974,226 | ||
| Auditor Name | Grant Thornton LLP | ||
| Auditor Location | Raleigh, North Carolina | ||
| Auditor Firm ID | 248 |
