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Acquisitions and Other Transactions (Matterhorn) (Details) - USD ($) $ in Millions		12 Months Ended
	Jun. 16, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Business Combination [Line Items]
Investments - acquisitions and contributions		$ 1,008	$ 464	$ 98
Natural Gas & NGL Services [Member]
Business Combination [Line Items]
Basis difference		$ 124	$ 198
MXP Parent, LLC
Business Combination [Line Items]
Equity Method Investment, Additional Ownership Acquired	5.00%
Ownership percentage	10.00%
Basis difference	$ 124
MXP Parent, LLC | Property, Plant and Equipment
Business Combination [Line Items]
Basis difference	63
MXP Parent, LLC | Customer-Related Intangible Assets
Business Combination [Line Items]
Basis difference	61
MXP Parent, LLC | Natural Gas & NGL Services [Member]
Business Combination [Line Items]
Investments - acquisitions and contributions	$ 151

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