Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Property, Plant and Equipment (Summary of Property, Plant and Equipment) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 31,759	$ 28,404
Less accumulated depreciation	10,061	9,250
Property, plant and equipment, net	21,698	19,154
Capitalized interest	42	19	$ 15
Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	13,809	13,189
Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	17,950	15,215
Pipelines And Related Assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	6,908	6,627
Refining Logistics and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,990	1,867
Terminals and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,869	1,726
Marine [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,188	1,149
Land Building Office Equipment And Other [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,627	1,619
Land Building Office Equipment And Other [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	437	541
Gas Gathering And Transportation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9,379	7,789
Processing and fractionation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	6,896	6,611
Construction-in-progress \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	227	201
Construction-in-progress \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 1,238	$ 274
Minimum \| Pipelines And Related Assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years
Minimum \| Refining Logistics and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years
Minimum \| Terminals and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years
Minimum \| Marine [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years
Minimum \| Land Building Office Equipment And Other [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Minimum \| Land Building Office Equipment And Other [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Minimum \| Gas Gathering And Transportation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Minimum \| Processing and fractionation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years
Maximum \| Pipelines And Related Assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	50 years
Maximum \| Refining Logistics and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years
Maximum \| Terminals and related assets [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Maximum \| Marine [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years
Maximum \| Land Building Office Equipment And Other [Member] \| Crude Oil and Products Logistics [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	50 years
Maximum \| Land Building Office Equipment And Other [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Maximum \| Gas Gathering And Transportation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Maximum \| Processing and fractionation [Member] \| Natural Gas & NGL Services [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years