Operating Segments - Segment Adjusted EBITDA Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting, Reconciling Item from Segments to Consolidated [Line Items]
Segment Adjusted EBITDA	$ 681	$ 727	$ 1,998	$ 2,371
Adjustments:
Depreciation and amortization of unconsolidated entities	(18)	(18)	(51)	(45)
Gains/(losses) from derivative activities, net of inventory valuation adjustments	(88)	29	(210)	60
Long-term inventory costing adjustments	(2)	1	(66)	(3)
Deficiencies under minimum volume commitments, net	(64)	4	(69)	10
Equity-indexed compensation expense	(5)	(5)	(13)	(13)
Net gain/(loss) on foreign currency revaluation	(4)	5	9	(7)
Significant acquisition-related expenses			(3)
Unallocated general and administrative expenses	(62)	(75)	(206)	(229)
Depreciation and amortization	(161)	(157)	(495)	(441)
Gains/(losses) on asset sales and asset impairments, net	2	7	(617)	7
Goodwill impairment losses	0	0	(2,515)	0
Gain on/(impairment of) investments in unconsolidated entities, net	(91)	4	(182)	271
Interest expense, net	(113)	(108)	(329)	(311)
Other income/(expense), net	5	5	(7)	23
INCOME/(LOSS) BEFORE TAX	141	493	(2,555)	1,908
Income tax (expense)/benefit	(2)	(62)	138	(137)
NET INCOME/(LOSS)	139	431	(2,417)	1,771
Net (income)/loss attributable to noncontrolling interests	(122)	(361)	1,869	(1,488)
NET INCOME/(LOSS) ATTRIBUTABLE TO PAGP	17	70	(548)	283
Line 901 Incident
Adjustments:
Line 901 incident				(10)
Unallocated
Adjustments:
Unallocated general and administrative expenses	$ (1)	$ (1)	$ (5)	$ (4)

Includes the impact of amounts billed to counterparties for their deficiency obligation, net of applicable amounts subsequently recognized into revenue. Certain agreements require counterparties to deliver, transport or throughput a minimum volume over an agreed upon period. Substantially all of such agreements were entered into with counterparties to economically support the return on the reporting entity's capital expenditure necessary to construct the related asset. Some of these agreements include make-up rights if the minimum volume is not met. A receivable from the counterparty is recorded in the period that services are provided or when the transaction occurs, including amounts for deficiency obligations from counterparties associated with minimum volume commitments. If a counterparty has a make-up right associated with a deficiency, the revenue attributable to the counterparty’s make-up right is deferred and is subsequently recognized at the earlier of when the deficiency volume is delivered or shipped, when the make-up right expires or when it is determined that the counterparty’s ability to utilize the make-up right is remote.

No definition available.