Related Party Transactions - Promissory Notes with Our General Partner (Details) - PAGP - Related Party Promissory Notes - General Partner - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Related Party Transaction [Line Items]
Related party notes receivable	$ 942	$ 1,339
Related party notes payable	$ 942	$ 1,339

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details