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Acquisitions and Other Transactions (Matterhorn) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Jun. 16, 2025
Business Combination [Line Items]
Investments - acquisitions and contributions	$ 776	$ 414
MXP Parent, LLC
Business Combination [Line Items]
Equity Method Investment, Addition Ownership Acquired			5.00%
Equity method investment, ownership percentage			10.00%
Difference between carrying amount and underlying equity			$ 124
MXP Parent, LLC | Property, Plant and Equipment
Business Combination [Line Items]
Difference between carrying amount and underlying equity			63
MXP Parent, LLC | Customer-Related Intangible Assets
Business Combination [Line Items]
Difference between carrying amount and underlying equity			$ 61

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