| Cover | Aug. 02, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | This Amendment No. 1 to Current Report on Form 8-K/A (the "8-K Amendment") is being filed to amend the Current Report on Form 8-K of Stagwell Inc. (the "Company") filed on August 2, 2021 (the "Original 8-K"). The Original 8-K included disclosure in Item 5.02 with respect to the appointments of Jay Leveton as President of the Company and Ryan Greene as Chief Operating Officer of the Company. This 8-K Amendment supplements and amends Item 5.02 to include information that became available after the filing of the Original 8-K with respect to the terms of the compensation agreements between the Company and Mr. Leveton and Mr. Greene. |
| Document Period End Date | Aug. 2, 2021 |
| Entity File Number | 001-13718 |
| Entity Registrant Name | STAGWELL INC. |
| Entity Central Index Key | 0000876883 |
| Entity Tax Identification Number | 86-1390679 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | One World Trade Center |
| Entity Address, Address Line Two | Floor 65 |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10007 |
| City Area Code | 646 |
| Local Phone Number | 429-1800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Common Stock, $0.001 par value |
| Trading Symbol | STGW |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
