Segment Information - Segment Financial Data (Details) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Sep. 30, 2021 segment	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Operating Segments
Operating segments number | segment	2	3	2
Revenues:
Total revenues			$ 42,078	$ 23,290	$ 33,669
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities			274	355	388
Segment Adjusted EBITDA			2,194	2,543	3,220
Investment and acquisition capital expenditures			269	1,231	1,390
Maintenance capital expenditures			168	216	287
Investments in unconsolidated entities	$ 3,805		3,805	3,764	3,683
Product sales
Revenues:
Total revenues			40,883	22,058	32,272
Services
Revenues:
Total revenues			1,195	1,232	1,397
Crude Oil
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities			274	355	388
Segment Adjusted EBITDA			1,909	2,216	2,753
Investment and acquisition capital expenditures			212	1,182	1,332
Maintenance capital expenditures			100	171	248
Investments in unconsolidated entities	3,805		3,805	3,764	3,683
NGL
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities			0	0	0
Segment Adjusted EBITDA			285	327	467
Investment and acquisition capital expenditures			57	49	58
Maintenance capital expenditures			68	45	39
Investments in unconsolidated entities	$ 0		0	0	0
Operating Segments
Revenues:
Total revenues			42,438	23,559	34,094
Operating Segments | Crude Oil
Revenues:
Total revenues			40,470	22,199	31,655
Operating Segments | Crude Oil | Product sales
Revenues:
Total revenues			39,395	21,089	30,375
Operating Segments | Crude Oil | Services
Revenues:
Total revenues			1,075	1,110	1,280
Operating Segments | NGL
Revenues:
Total revenues			1,968	1,360	2,439
Operating Segments | NGL | Product sales
Revenues:
Total revenues			1,829	1,218	2,302
Operating Segments | NGL | Services
Revenues:
Total revenues			139	142	137
Intersegment Revenues Elimination
Revenues:
Total revenues			(360)	(269)	(425)
Intersegment Revenues Elimination | Product sales
Revenues:
Total revenues			(341)	(249)	(405)
Intersegment Revenues Elimination | Services
Revenues:
Total revenues			$ (19)	$ (20)	$ (20)