| Document and Entity Information | Jun. 19, 2020 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001549922 |
| Document Type | 8-K |
| Document Period End Date | Jun. 19, 2020 |
| Entity Registrant Name | Summit Midstream Partners, LP |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-35666 |
| Entity Tax Identification Number | 45-5200503 |
| Entity Address, Address Line One | 910 Louisiana Street |
| Entity Address, Address Line Two | Suite 4200 |
| Entity Address, City or Town | Houston |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77002 |
| City Area Code | (832) |
| Local Phone Number | 413-4770 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Units |
| Trading Symbol | SMLP |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
