Segment Information - Segment Financial Data (Details) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)	Mar. 31, 2022 segment	Sep. 30, 2021 segment
Segment Reporting Information
Operating segments number | segment	2		2	3
Revenues:
Revenues	$ 13,694	$ 8,383
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities	97	88
Segment Adjusted EBITDA	614	543
Maintenance capital expenditures	27	35
Operating Segments
Revenues:
Revenues	13,814	8,492
Intersegment Revenues Elimination
Revenues:
Revenues	(120)	(109)
Product sales revenues
Revenues:
Revenues	13,381	8,083
Product sales revenues | Intersegment Revenues Elimination
Revenues:
Revenues	(112)	(103)
Services revenues
Revenues:
Revenues	313	300
Services revenues | Intersegment Revenues Elimination
Revenues:
Revenues	(8)	(6)
Crude Oil
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities	97	88
Segment Adjusted EBITDA	453	474
Maintenance capital expenditures	19	28
Crude Oil | Operating Segments
Revenues:
Revenues	13,079	7,853
Crude Oil | Product sales revenues | Operating Segments
Revenues:
Revenues	12,811	7,586
Crude Oil | Services revenues | Operating Segments
Revenues:
Revenues	268	267
NGL
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities	0	0
Segment Adjusted EBITDA	161	69
Maintenance capital expenditures	8	7
NGL | Operating Segments
Revenues:
Revenues	735	639
NGL | Product sales revenues | Operating Segments
Revenues:
Revenues	682	600
NGL | Services revenues | Operating Segments
Revenues:
Revenues	$ 53	$ 39