| Cover Page Cover Page | Oct. 31, 2019 |
| Entity Listings [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Oct. 31, 2019 |
| Entity Registrant Name | Magellan Midstream Partners, L.P. |
| Entity Central Index Key | 0001126975 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-16335 |
| Entity Tax Identification Number | 73-1599053 |
| Entity Address, Address Line One | One Williams Center |
| Entity Address, City or Town | Tulsa |
| Entity Address, State or Province | OK |
| Entity Address, Postal Zip Code | 74172 |
| City Area Code | 918 |
| Local Phone Number | 574-7000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| NEW YORK STOCK EXCHANGE, INC. [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Common Units representing limited partnership interests |
| Trading Symbol | MMP |
| Security Exchange Name | NYSE |
