v3.8.0.1

Related-Party Transactions Related-Party Transactions, Summary of Transactions Narrative (Details) - USD ($)
$ in Millions

3 Months Ended

9 Months Ended

Sep. 30, 2017

Sep. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Revenue from Related Parties

^[1]

$ 219

$ 184

^[2]

$ 624

$ 521

^[2]

Related Party Transaction, Expenses from Transactions with Related Party

^[3]

32

38

109

107

Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party

$ 20

$ 19

$ 58

52

Concentration Risk, Percentage

49.00%

60.00%

49.00%

Cost of Reimbursable Expense

$ 7

$ 3

$ 12

12

Partner to Andeavor [Member] | Omnibus Agreement

Payment for Administrative Fees

11

Andeavor to Partner | Secondment and Logistics Services Agreement

Long-term Purchase Commitment, Amount

$ 6

$ 1

$ 16

$ 7

[1]	Andeavor accounted for 49% and 60% of our total revenues for the three months ended September 30, 2017 and 2016, respectively, and 49% and 58% for the nine months ended September 30, 2017 and 2016, respectively.
[2]	Adjusted to include the historical results of the Predecessors. See Note 1 for further discussion.
[3]	reimbursements from Andeavor pursuant to the Amended Omnibus Agreement, the Carson Assets Indemnity Agreement and other affiliate agreements of $7 million and $3 million for the three months ended September 30, 2017 and 2016, respectively, and $12 million for both the nine months ended September 30, 2017 and 2016.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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+ References

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