| Cover Page | Aug. 04, 2020 | May 05, 2020 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Document Period End Date | Aug. 4, 2020 | |
| Entity Registrant Name | PLAINS GP HOLDINGS LP | |
| Entity Incorporation, State or Country Code | DE | |
| Entity File Number | 1-36132 | |
| Entity Tax Identification Number | 90-1005472 | |
| Entity Address, Address Line One | 333 Clay Street | |
| Entity Address, Address Line Two | Suite 1600 | |
| Entity Address, City or Town | Houston | |
| Entity Address, State or Province | TX | |
| Entity Address, Postal Zip Code | 77002 | |
| City Area Code | 713 | |
| Local Phone Number | 646-4100 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Entity Emerging Growth Company | false | |
| Title of 12(b) Security | Class A Shares | |
| Trading Symbol | PAGP | |
| Security Exchange Name | NYSE | |
| Entity Central Index Key | 0001581990 | |
| Amendment Flag | false |
