Commitments and Contingencies (Guarantees) (Details) $ in Millions	Dec. 31, 2023 USD ($)
Crowley Blue Water Partners
Loss Contingencies [Line Items]
Equity method investments, ownership percentage	50.00%
Financial Guarantee \| Guarantee of Indebtedness of Others \| LOOP and LOCAP LLC
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 222
Financial Guarantee \| Guarantee of Indebtedness of Others \| Bakken Pipeline System
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	170
Financial Guarantee \| Guarantee of Indebtedness of Others \| Crowley Blue Water Partners
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	94
Other Guarantees
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 113
Indirect \| Bakken Pipeline System
Loss Contingencies [Line Items]
Equity method investments, ownership percentage	9.19%

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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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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