| Document and Entity Information Document | Aug. 01, 2019 |
| Cover page. | |
| Document Type | 8-K |
| Document Period End Date | Aug. 1, 2019 |
| Entity Registrant Name | TREEHOUSE FOODS, INC. |
| Entity File Number | 001-32504 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 20-2311383 |
| Entity Address, Address Line One | 2021 Spring RoadSuite 600 |
| Entity Address, City or Town | Oak Brook |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60523 |
| City Area Code | 708 |
| Local Phone Number | 483-1300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | THS |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001320695 |
| Amendment Flag | false |
