Consolidated Statements of Equity and Redeemable Noncontrolling Interest (Consolidated Statements of Equity) - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Non-controlling Interests
Beginning balance at Dec. 31, 2020	$ 29,252	$ 10	$ (15,157)	$ 33,208	$ 4,650	$ (512)	$ 7,053
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	44				(242)		286
Dividends declared on common stock	(379)				(379)
Distributions to noncontrolling interests	(300)						(300)
Other comprehensive income (loss)	1					1
Shares returned - stock based compensation			(1)				0
Shares issued - stock based compensation				18
Net shares issued - stock based compensation	17
Equity transactions of MPLX	(124)			(4)			(120)
Ending balance at Mar. 31, 2021	28,511	10	(15,158)	33,222	4,029	(511)	6,919
Beginning balance at Dec. 31, 2020	29,252	10	(15,157)	33,208	4,650	(512)	7,053
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	172
Equity transactions of MPLX				(38)
Ending balance at Jun. 30, 2021	35,725	10	(16,147)	33,238	12,160	(340)	6,804
Beginning balance at Mar. 31, 2021	28,511	10	(15,158)	33,222	4,029	(511)	6,919
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	8,781				8,512		269
Dividends declared on common stock	(381)				(381)
Distributions to noncontrolling interests	(272)						(272)
Other comprehensive income (loss)	171					171
Shares repurchased	(984)		(984)
Shares returned - stock based compensation			(5)
Shares issued - stock based compensation				50
Net shares issued - stock based compensation	47						2
Equity transactions of MPLX	(148)			(34)			(114)
Ending balance at Jun. 30, 2021	35,725	10	(16,147)	33,238	12,160	(340)	6,804
Beginning balance at Dec. 31, 2021	32,616	10	(19,904)	33,262	12,905	(67)	6,410
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,151				845		306
Dividends declared on common stock	(330)				(330)
Distributions to noncontrolling interests	(290)						(290)
Other comprehensive income (loss)	(7)					(7)
Shares repurchased	(2,807)		(2,807)
Shares returned - stock based compensation			0				(1)
Shares issued - stock based compensation				90
Net shares issued - stock based compensation	89
Equity transactions of MPLX	(88)			(25)			(63)
Ending balance at Mar. 31, 2022	30,334	10	(22,711)	33,327	13,420	(74)	6,362
Beginning balance at Dec. 31, 2021	32,616	10	(19,904)	33,262	12,905	(67)	6,410
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	2
Equity transactions of MPLX				(45)
Ending balance at Jun. 30, 2022	32,704	10	(26,000)	33,378	18,983	(65)	6,398
Beginning balance at Mar. 31, 2022	30,334	10	(22,711)	33,327	13,420	(74)	6,362
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	6,196				5,873		323
Dividends declared on common stock	(310)				(310)
Distributions to noncontrolling interests	(267)						(267)
Other comprehensive income (loss)	9					9
Shares repurchased	(3,285)		(3,285)
Shares returned - stock based compensation			(4)
Shares issued - stock based compensation				71
Net shares issued - stock based compensation	69						2
Equity transactions of MPLX	(42)			(20)			(22)
Ending balance at Jun. 30, 2022	$ 32,704	$ 10	$ (26,000)	$ 33,378	$ 18,983	$ (65)	$ 6,398