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- Definition

Represents the number of assets relating to a particular asset category used in an operating segment.

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- Definition

Number Of Miles

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No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Amount per share or per unit assigned to the consideration received of equity securities issued for development stage entities.

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The number of general partner units issued.

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The number of general partner units outstanding.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The number of limited partner units outstanding.

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- Definition

Monetary value of the issuance of new units of limited partnership interest in a public offering, net of offering costs. This is a parenthetical disclosure.

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- Definition

The number of units sold in a public offering of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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

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Tesoro Logistics LP, Narrative (Details) $ / shares in Units, $ in Millions					3 Months Ended	12 Months Ended
	Apr. 06, 2015	Oct. 19, 2014	Nov. 22, 2013 USD ($) $ / shares shares	Jan. 14, 2013 USD ($) $ / shares shares	Mar. 31, 2015 USD ($) mi terminals pipelines shares	Dec. 31, 2014 USD ($) terminals shares	Dec. 02, 2014 shares	Oct. 29, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jun. 01, 2013 entities
Capital Unit
Number of assets \| entities										6
Percentage ownership					36.00%	36.00%
Limited partner common units outstanding (units)					28,181,748	28,181,748
General partner units outstanding (units)						1,631,448
Debt instrument, face amount \| $								$ 1,300
Goodwill \| $						$ 196			$ 41
Common units issued in offering (units)			6,300,000	9,775,000
Price per unit (dollars per unit) \| $ / shares			$ 51.05	$ 41.70
Net proceeds from issuance of units \| $			$ 310	$ 391
General partners' capital account, units issued (units)				199,490
Purchase agreement date		Oct. 19, 2014
TLGP
Capital Unit
Percentage ownership						2.00%
General partner units outstanding (units)					1,631,448
Subsequent Event
Capital Unit
Purchase agreement date	Apr. 06, 2015
Common Units Conversion Ratio	0.3088
Crude Oil and Refined Products Terminals and Storage Facilities \| TLLP
Capital Unit
Number of assets \| terminals					24	24
Common carrier products pipeline \| TLLP
Capital Unit
Number of assets \| pipelines					1
Gas Processing Complexes \| TLLP
Capital Unit
Number of assets \| terminals					4
Pipelines \| TLLP
Capital Unit
Number of assets \| pipelines					1
Marine terminals \| TLLP
Capital Unit
Number of assets \| terminals					4	4
Pipeline Transportation of Refined Petroleum Products and Crude Oil \| TLLP
Capital Unit
Number of miles (miles) \| mi					140
Rockies Natural Gas Business
Capital Unit
Limited partner common units outstanding (units)							3,701,750
Goodwill \| $					$ 159	$ 155