Commitments and Contingencies (Guarantees) (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 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]
Line of credit facility, expiration date	Dec. 31, 2037
Financial Guarantee \| Guarantee of Indebtedness of Others \| Crowley Ocean Partners \| Crowley Term Loan
Loss Contingencies [Line Items]
Line of credit facility, maximum borrowing capacity	$ 325
Indemnification Agreement \| Marathon Oil Companies
Loss Contingencies [Line Items]
Guarantee obligation current carrying value	2
Other Guarantees
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	123
Guarantee of Indebtedness of Others \| Financial Guarantee \| LOOP and LOCAP LLC
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	171
Guarantee of Indebtedness of Others \| Financial Guarantee \| Crowley Ocean Partners
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	163
Guarantee of Indebtedness of Others \| Financial Guarantee \| Crowley Blue Water Partners
Loss Contingencies [Line Items]
Maximum potential undiscounted payments	$ 128

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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-Publisher FASB
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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Date the credit facility terminates, in CCYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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