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Commitments and Contingencies - Guarantees (Details) $ in Millions | Sep. 30, 2019 USD ($)
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Other Guarantees |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 122
LOOP and LOCAP LLC | Guarantee of Indebtedness of Others | Financial Guarantee |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 171
Gray Oak Pipeline |
Loss Contingencies [Line Items] |
Equity method investments, ownership percentage | 25.00%
Gray Oak Pipeline | Guarantee of Indebtedness of Others | Financial Guarantee |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 226
Maximum borrowing capacity | 1,430
Bakken Pipeline System | Other Guarantees |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 230
Crowley Ocean Partners |
Loss Contingencies [Line Items] |
Equity method investments, ownership percentage | 50.00%
Crowley Ocean Partners | Guarantee of Indebtedness of Others | Financial Guarantee |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 125
Crowley Ocean Partners | Guarantee of Indebtedness of Others | Financial Guarantee | Crowley Term Loan |
Loss Contingencies [Line Items] |
Maximum borrowing capacity | $ 325
Crowley Blue Water Partners |
Loss Contingencies [Line Items] |
Equity method investments, ownership percentage | 50.00%
Crowley Blue Water Partners | Guarantee of Indebtedness of Others | Financial Guarantee |
Loss Contingencies [Line Items] |
Maximum potential undiscounted payments | $ 122
Indirect Ownership Interest | Bakken Pipeline System |
Loss Contingencies [Line Items] |
Equity method investments, ownership percentage | 9.00%
Marathon Oil Companies | Indemnification Agreement |
Loss Contingencies [Line Items] |
Guarantee obligation current carrying value | $ 1

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