Redeemable Noncontrolling Interest - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Temporary Equity [Abstract]
Beginning balance	$ 1,000	$ 1,000	$ 0
Net income (loss) attributable to redeemable noncontrolling interest	75	65	41
Distributions to noncontrolling interests	(71)	(65)	(25)
Issuance of MPLX LP redeemable preferred units			984
Ending balance	$ 1,004	$ 1,000	$ 1,000