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- Definition

Gain (loss) on issuance of equity by equity method investee

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- Definition

Incremental capacity expected to be added

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- Definition

Number of Seats on the Board of Directors

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- Definition

Pipeline capacity

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- Definition

Transaction related costs

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- Definition

Units of equity investee divested

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- Definition

Width of Pipeline

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- Definition

Amount of accumulated interest costs capitalized as part of property, plant and equipment cost basis.

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

+ 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)(3)

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- Definition

This item represents the amount of net sales proceeds received on disposal of an equity method investment.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 35

-Paragraph 35

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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.

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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

This item represents the aggregate value of each identified investment accounted for under the equity method of accounting based on the quoted market price for those investments in common stock for which a quoted market price is available.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

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No definition available.

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.4)

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- Definition

Number of shares of affiliates held for management investment companies.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column B

-Article 12

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- Definition

Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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Price of a single share of a number of saleable stocks of a company.

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Equity Method Investments (Details Textual) (USD $)	3 Months Ended								12 Months Ended			3 Months Ended
Equity Method Investments (Details Textual) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2015	Oct. 27, 2014
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Gain on issuance of common units by equity method investee	$ 2,121,000	$ 18,772,000	$ 0	$ 8,127,000	$ 26,873,000	$ 0	$ 0	$ 0	$ 29,020,000	$ 26,873,000	$ 0
General and administrative expenses									87,845,000us-gaap_GeneralAndAdministrativeExpense	78,597,000us-gaap_GeneralAndAdministrativeExpense	71,918,000us-gaap_GeneralAndAdministrativeExpense
Share price	$ 68.39us-gaap_SharePrice								$ 68.39us-gaap_SharePrice
Proceeds from Sale of Equity Method Investments									79,741,000	0	0
Equity Method Investment, Realized Gain (Loss) on Disposal									34,211,000	0	0
White Cliffs Pipeline, LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
General and administrative expenses									1,600,000	1,800,000	2,000,000
SemStream [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Gain on issuance of common units by equity method investee									29,020,000	26,873,000
General and administrative expenses									83,000	600,000	930,000
White Cliffs Pipeline, LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Percentage of ownership interest	51.00%								51.00%
Width of Pipeline									12
Ngl Energy Partners Lp [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Gain on issuance of common units by equity method investee									29,000,000	26,900,000
Share price	$ 27.99								$ 27.99
Units of equity investee divested									2,481,308
Proceeds from Sale of Equity Method Investments									88,800,000
Proceeds from Sale of Equity Method Investments									79,700,000
Ngl Energy Partners Lp [Member] \| NGL Energy Holdings LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Number of Seats on the Board of Directors													2
Ngl Energy Partners Lp [Member] \| Subsequent Event [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Units of equity investee divested												999,533
Proceeds from Sale of Equity Method Investments												29,000,000
Transaction related costs												400,000
Equity Method Investment, Realized Gain (Loss) on Disposal												7,500,000
Glass Mountain Pipeline LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Partners' Capital Account, Contributions									16,200,000	57,800,000
Equity Method Goodwill	31,000,000								31,000,000
Accumulated Capitalized Interest Costs	4,100,000								4,100,000
Partnership Interest [Member] \| Glass Mountain Pipeline LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Percentage of ownership interest	50.00%								50.00%
Limited Partner [Member] \| Partnership Interest [Member] \| Ngl Energy Partners Lp [Member] \| SemStream [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Percentage of ownership interest		7.50%
Investments in and Advances to Affiliates, Balance, Shares	6,652,101								6,652,101
General Partner [Member] \| Ngl Energy Partners Lp [Member] \| SemStream [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Percentage of ownership interest	11.78%								11.78%
Pipeline expansion [Member] \| White Cliffs Pipeline, LLC [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Incremental capacity expected to be added									65,000
Expected capital contributions, year one									40,000,000
Pipeline capacity	150,000								150,000
Partners' Capital Account, Contributions									53,300,000	95,500,000	2,300,000
Other Nonoperating Income (Expense) [Member] \| Ngl Energy Partners Lp [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Transaction related costs									3,100,000
Equity Method Investment, Realized Gain (Loss) on Disposal									34,200,000
Fair Value, Inputs, Level 1 [Member] \| Ngl Energy Partners Lp [Member]
Investment in Non Consolidated Subsidiaries (Textual) [Abstract]
Equity Method Investment, Quoted Market Value	$ 186,200,000								$ 186,200,000