Business Segments and Related Information - Schedule of Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment revenues:
Revenues	$ 12,023	$ 13,775	$ 38,803	$ 42,018
Significant segment expenses:
Cost of sales	8,590	10,387	28,494	31,976
Other segment income (expense):
Equity in income of unconsolidated affiliates	90	99	276	302
NGL Pipelines & Services
Segment revenues:
Revenues	3,465	4,831	12,271	14,236
Other segment income (expense):
Equity in income of unconsolidated affiliates	21	27	59	84
Crude Oil Pipelines & Services
Segment revenues:
Revenues	5,396	5,251	15,300	16,554
Other segment income (expense):
Equity in income of unconsolidated affiliates	68	70	212	212
Natural Gas Pipelines & Services
Segment revenues:
Revenues	932	649	3,224	2,115
Other segment income (expense):
Equity in income of unconsolidated affiliates	2	2	4	5
Petrochemical & Refined Products Services
Segment revenues:
Revenues	2,230	3,044	8,008	9,113
Other segment income (expense):
Equity in income of unconsolidated affiliates	(1)	0	1	1
Nonrelated Party
Segment revenues:
Revenues	12,009	13,759	38,765	41,976
Related parties
Segment revenues:
Revenues	14	16	38	42
Operating Segments
Segment revenues:
Revenues	45,364	45,607	139,537	138,185
Significant segment expenses:
Cost of sales	41,643	41,969	128,388	127,364
Variable operating costs and expenses	394	322	1,121	953
Fixed operating costs and expenses	1,048	961	3,051	2,812
Total significant segment expenses	43,085	43,252	132,560	131,129
Other segment income (expense):
Equity in income of unconsolidated affiliates	90	99	276	302
Other segment items	14	(6)	65	24
Total other segment income (expense), net	104	93	341	326
Total segment gross operating margin	2,383	2,448	7,318	7,382
Other financial information:
Capital expenditures	1,958	1,174	4,319	3,485
Operating Segments | NGL Pipelines & Services
Segment revenues:
Revenues	21,048	15,875	63,875	48,393
Significant segment expenses:
Cost of sales	19,093	13,946	58,013	42,713
Variable operating costs and expenses	219	190	622	531
Fixed operating costs and expenses	456	425	1,321	1,254
Total significant segment expenses	19,768	14,561	59,956	44,498
Other segment income (expense):
Equity in income of unconsolidated affiliates	21	27	59	84
Other segment items	2	(6)	40	21
Total other segment income (expense), net	23	21	99	105
Total segment gross operating margin	1,303	1,335	4,018	4,000
Other financial information:
Capital expenditures	1,097	629	2,557	1,835
Operating Segments | Crude Oil Pipelines & Services
Segment revenues:
Revenues	16,900	18,929	46,750	59,101
Significant segment expenses:
Cost of sales	16,450	18,463	45,417	57,679
Variable operating costs and expenses	36	30	105	102
Fixed operating costs and expenses	116	103	305	310
Total significant segment expenses	16,602	18,596	45,827	58,091
Other segment income (expense):
Equity in income of unconsolidated affiliates	68	70	212	212
Other segment items	5	(2)	13	7
Total other segment income (expense), net	73	68	225	219
Total segment gross operating margin	371	401	1,148	1,229
Other financial information:
Capital expenditures	35	52	83	133
Operating Segments | Natural Gas Pipelines & Services
Segment revenues:
Revenues	1,167	815	3,893	2,596
Significant segment expenses:
Cost of sales	616	279	2,159	1,106
Variable operating costs and expenses	21	15	63	54
Fixed operating costs and expenses	194	174	566	492
Total significant segment expenses	831	468	2,788	1,652
Other segment income (expense):
Equity in income of unconsolidated affiliates	2	2	4	5
Other segment items	1	0	4	5
Total other segment income (expense), net	3	2	8	10
Total segment gross operating margin	339	349	1,113	954
Other financial information:
Capital expenditures	674	246	1,304	696
Operating Segments | Petrochemical & Refined Products Services
Segment revenues:
Revenues	6,249	9,988	25,019	28,095
Significant segment expenses:
Cost of sales	5,484	9,281	22,799	25,866
Variable operating costs and expenses	118	87	331	266
Fixed operating costs and expenses	282	259	859	756
Total significant segment expenses	5,884	9,627	23,989	26,888
Other segment income (expense):
Equity in income of unconsolidated affiliates	(1)	0	1	1
Other segment items	6	2	8	(9)
Total other segment income (expense), net	5	2	9	(8)
Total segment gross operating margin	370	363	1,039	1,199
Other financial information:
Capital expenditures	152	247	375	821
Operating Segments | Nonrelated Party
Segment revenues:
Revenues	12,009	13,759	38,765	41,976
Operating Segments | Nonrelated Party | NGL Pipelines & Services
Segment revenues:
Revenues	3,463	4,828	12,265	14,227
Operating Segments | Nonrelated Party | Crude Oil Pipelines & Services
Segment revenues:
Revenues	5,389	5,241	15,281	16,530
Operating Segments | Nonrelated Party | Natural Gas Pipelines & Services
Segment revenues:
Revenues	927	646	3,211	2,106
Operating Segments | Nonrelated Party | Petrochemical & Refined Products Services
Segment revenues:
Revenues	2,230	3,044	8,008	9,113
Operating Segments | Related parties
Segment revenues:
Revenues	14	16	38	42
Operating Segments | Related parties | NGL Pipelines & Services
Segment revenues:
Revenues	2	3	6	9
Operating Segments | Related parties | Crude Oil Pipelines & Services
Segment revenues:
Revenues	7	10	19	24
Operating Segments | Related parties | Natural Gas Pipelines & Services
Segment revenues:
Revenues	5	3	13	9
Operating Segments | Related parties | Petrochemical & Refined Products Services
Segment revenues:
Revenues	0	0	0	0
Intersegment Eliminations
Segment revenues:
Revenues	(33,341)	(31,832)	(100,734)	(96,167)
Intersegment Eliminations | NGL Pipelines & Services
Segment revenues:
Revenues	(17,583)	(11,044)	(51,604)	(34,157)
Intersegment Eliminations | Crude Oil Pipelines & Services
Segment revenues:
Revenues	(11,504)	(13,678)	(31,450)	(42,547)
Intersegment Eliminations | Natural Gas Pipelines & Services
Segment revenues:
Revenues	(235)	(166)	(669)	(481)
Intersegment Eliminations | Petrochemical & Refined Products Services
Segment revenues:
Revenues	$ (4,019)	$ (6,944)	$ (17,011)	$ (18,982)