Net Income Per Class A Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Basic and Diluted Net Income per Class A Share
Net income attributable to PAGP	$ 103	$ 198	$ 168
AAP Units | Weighted Average
Basic and diluted earnings per share
Antidilutive securities excluded from computation of earnings per share (in shares)	35	44	47
Class A Shares
Basic and Diluted Net Income per Class A Share
Basic weighted average Class A shares outstanding (in shares)	197	195	194
Diluted weighted average Class A shares outstanding (in shares)	197	195	194
Basic net income per Class A share (in dollars per share)	$ 0.52	$ 1.01	$ 0.86
Diluted net income per Class A share (in dollars per share)	$ 0.52	$ 1.01	$ 0.86