Investments in Unconsolidated Affiliates - Additional Information (Details) - Targa Resources Partners LP [Member] $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) JointVenture
Gulf Coast Fractionators LP [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	38.80%
T2 Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Number of non-operated joint ventures acquired in Atlas mergers \| JointVenture	3
Basis difference on preliminary fair values \| $	$ 36.2
Preliminary estimated useful lives of the underlying assets	20 years
T2 LaSalle [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	75.00%
T2 Eagle Ford [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	50.00%
T2 EF Cogen [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	50.00%

The estimated periods of time over which underlying assets amortized on a straight-line basis.

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- Definition

Represents the number of non-operated joint ventures acquired in Atlas mergers.

+ References

No definition available.

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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)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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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)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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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.

+ References

No definition available.

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