Commitments and Contingencies (Guarantees) (Details) $ in Millions	Sep. 30, 2024 USD ($)
Other Guarantees
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 192
LOOP and LOCAP LLC \| Guarantee of Indebtedness of Others \| Financial Guarantee
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 222
Bakken Pipeline System \| Indirect
Loss Contingencies [Line Items]
Ownership percentage	9.19%
Bakken Pipeline System \| Guarantee of Indebtedness of Others \| Financial Guarantee
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 78
Crowley Blue Water Partners
Loss Contingencies [Line Items]
Ownership percentage	50.00%
Crowley Blue Water Partners \| Guarantee of Indebtedness of Others \| Financial Guarantee
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 87

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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