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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

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Consolidation And Basis Of Presentation (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Consolidation And Basis Of Presentation [Line Items]
Property, plant and equipment	$ 1,256,825,000us-gaap_PropertyPlantAndEquipmentNet	$ 1,105,728,000us-gaap_PropertyPlantAndEquipmentNet
SemCAMS [Member] \| Proportionally Consolidated Assets [Member]
Consolidation And Basis Of Presentation [Line Items]
Property, plant and equipment	209,800,000
White Cliffs Pipeline, LLC [Member]
Consolidation And Basis Of Presentation [Line Items]
Equity method investment, ownership percentage	51.00%
White Cliffs Pipeline, LLC [Member] \| Semcrude Pipeline [Member]
Consolidation And Basis Of Presentation [Line Items]
Equity method investment, ownership percentage	51.00%
White Cliffs Pipeline, LLC [Member] \| Crude [Member]
Consolidation And Basis Of Presentation [Line Items]
Equity method investment, ownership percentage	51.00%
Glass Mountain Pipeline LLC [Member] \| Crude [Member]
Consolidation And Basis Of Presentation [Line Items]
Equity method investment, ownership percentage	50.00%
Semcrude Pipeline [Member] \| Common control transaction [Member] \| Rose Rock Midstream L P [Member]
Consolidation And Basis Of Presentation [Line Items]
Gain (loss) sale of interest in SemCrude Pipeline, L.L.C. to subsidiary	$ 0