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Commitments and Contingencies - Guarantees (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2017 | May 01, 2016 | Sep. 30, 2015
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 | 83 |  |
Guarantee obligations maximum exposure per event | $ 50 |  |
LOOP and LOCAP LLC | Guarantee of Indebtedness of Others | Financial Guarantee |  |  |
Loss Contingencies [Line Items] |  |  |
Line of credit facility, expiration date | Dec. 31, 2037 |  |
Maximum potential undiscounted payments | $ 172 |  |
Centennial | Guarantee of Indebtedness of Others | Financial Guarantee |  |  |
Loss Contingencies [Line Items] |  |  |
Maximum potential undiscounted payments | $ 24 |  |
Centennial | Master Shelf Agreement [Member] | Financial Guarantee |  |  |
Loss Contingencies [Line Items] |  |  |
Line of credit facility, expiration date | Dec. 31, 2024 |  |
Crowley Ocean Partners |  |  |
Loss Contingencies [Line Items] |  |  |
Equity method investments, ownership percentage | 50.00% | 50.00% | 50.00%
Crowley Ocean Partners | Guarantee of Indebtedness of Others | Financial Guarantee |  |  |
Loss Contingencies [Line Items] |  |  |
Maximum potential undiscounted payments | $ 163 |  |
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 | $ 139 |  |

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