Condensed Consolidating Financial Information, Narrative (Details)	12 Months Ended
Dec. 31, 2014
Guarantor Information
Percentage ownership of Tesoro Logistics LP	36.00%
Percentage ownership of subsidiary guarantors	100.00%
4.250% Senior Notes due 2017
Guarantor Information
Debt Instrument, Maturity Date	Oct. 01, 2017
5.375% Senior Notes due 2022
Guarantor Information
Debt Instrument, Maturity Date	Oct. 01, 2022
5.125% Senior Notes due 2024
Guarantor Information
Debt Instrument, Maturity Date	Apr. 01, 2024

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=SL6759159-111685

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