v3.8.0.1

Debt (Tables) | 9 Months Ended
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Sep. 30, 2017
Debt Disclosure [Abstract] |
Schedule of Debt | DEBT BALANCE, NET OF UNAMORTIZED ISSUANCE COSTS (in millions)
| September 30, 2017 |  | December 31, 2016
Total debt | $ | 4,134 |  |  | $ | 4,109 |
Unamortized issuance costs and premium (a) | (22 | ) |  | (55 | )
Current maturities | (1 | ) |  | (1 | )
Debt, Net of Current Maturities and Unamortized Issuance Costs | $ | 4,111 |  |  | $ | 4,053 |
(a) | Includes premium of $25 million related to the incremental fair value of the WNRL senior notes upon acquisition.
Line of Credit Facility [Line Items] |
Schedule of Line of Credit Facilities [Table Text Block] | AVAILABLE CAPACITY UNDER CREDIT FACILITIES (in millions)
| Total Capacity |  | Amount Borrowed as of September 30, 2017 |  | Outstanding Letters of Credit |  | Available Capacity as of September 30, 2017 |  | Expiration
Andeavor Logistics Revolving Credit Facility (a) | $ | 600 |  |  | $ | 35 |  |  | $ | — |  |  | $ | 565 |  |  | January 29, 2021
Andeavor Logistics Dropdown Credit Facility | 1,000 |  |  | — |  |  | — |  |  | 1,000 |  |  | January 29, 2021
WNRL Revolving Credit Facility (a) | 500 |  |  | 20 |  |  | 1 |  |  | 479 |  |  | October 16, 2018
Total Credit Facilities (b) | $ | 2,100 |  |  | $ | 55 |  |  | $ | 1 |  |  | $ | 2,044 |  |  |
(a) | The weighted average interest rates for borrowings under the Andeavor Logistics Revolving Credit Facility and the WNRL Revolving Credit Facility were 3.49% and 3.24%, respectively, at September 30, 2017.
(b) | We are allowed to request that the loan availability be increased up to an aggregate of $2.3 billion, subject to receiving increased commitments from the lenders.

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