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 | $ | 3,814 |  |  | $ | 4,109 |
Unamortized issuance costs | (48 | ) |  | (55 | )
Current maturities | (1 | ) |  | (1 | )
Debt, Net of Current Maturities and Unamortized Issuance Costs | $ | 3,765 |  |  | $ | 4,053 |
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
Total Credit Facilities (b) | $ | 1,600 |  |  | $ | 35 |  |  | $ | — |  |  | $ | 1,565 |  |  |
(a) | The weighted average interest rate for borrowings under our Revolving Credit Facility was 3.49% at September 30, 2017.
(b) | We are allowed to request that the loan availability be increased up to an aggregate of $2.1 billion, subject to receiving increased commitments from the lenders.

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