CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
REVENUES
Total revenues	$ 9,930	$ 3,225	$ 18,313	$ 11,494
COSTS AND EXPENSES
Purchases and related costs	9,277	2,525	16,669	9,893
Field operating costs	252	253	471	557
General and administrative expenses	74	74	142	144
Depreciation and amortization	197	166	375	335
(Gains)/losses on asset sales and asset impairments, net	369	(1)	370	618
Goodwill impairment losses				2,515
Total costs and expenses	10,169	3,017	18,027	14,062
OPERATING INCOME/(LOSS)	(239)	208	286	(2,568)
OTHER INCOME/(EXPENSE)
Equity earnings in unconsolidated entities	33	81	121	191
Gain on/(impairment of) investments in unconsolidated entities, net		(69)		(91)
Interest expense (net of capitalized interest of $5, $5, $10 and $11, respectively)	(107)	(108)	(213)	(215)
Other income/(expense), net	84	18	23	(13)
INCOME/(LOSS) BEFORE TAX	(229)	130	217	(2,696)
Current income tax expense	(1)	(15)	(3)	(22)
Deferred income tax (expense)/benefit	18	22	(33)	162
NET INCOME/(LOSS)	(212)	137	181	(2,556)
Net (income)/loss attributable to noncontrolling interests	143	(121)	(180)	1,991
NET INCOME/(LOSS) ATTRIBUTABLE TO PAGP	$ (69)	$ 16	$ 1	$ (565)
Class A Shares
OTHER INCOME/(EXPENSE)
BASIC NET INCOME/(LOSS) PER CLASS A SHARE (in dollars per share)	$ (0.35)	$ 0.09	$ 0	$ (3.08)
DILUTED NET INCOME/(LOSS) PER CLASS A SHARE (in dollars per share)	$ (0.35)	$ 0.09	$ 0	$ (3.08)
BASIC WEIGHTED AVERAGE CLASS A SHARES OUTSTANDING (in shares)	194	184	194	183
DILUTED WEIGHTED AVERAGE CLASS A SHARES OUTSTANDING (in shares)	194	184	194	183
Supply and Logistics
REVENUES
Total revenues	$ 9,623	$ 2,925	$ 17,706	$ 10,833
Transportation
REVENUES
Total revenues	162	151	299	338
OTHER INCOME/(EXPENSE)
Equity earnings in unconsolidated entities	31	81	117	189
Facilities
REVENUES
Total revenues	145	149	308	323
OTHER INCOME/(EXPENSE)
Equity earnings in unconsolidated entities	$ 2	$ 0	$ 4	$ 2