Equity Method Investments, Number of Investments

No definition available.

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- Definition

Represents the contribution cap of investment.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of expected contribution to be made by the entity for fund cost associated with the jointly owned pipeline in future years.

+ References

No definition available.

+ Details

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- Definition

The proportionate share of interest (percent) in a jointly owned pipeline.

+ References

No definition available.

+ Details

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- Definition

Represents the period for which the investment is expected for contribution.

+ References

No definition available.

+ Details

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 35
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=99375318&loc=d3e32787-111569

+ Details

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Period Type:	duration

- 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

+ Details

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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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Equity Method Investments - Narrative (Details)	1 Months Ended	12 Months Ended
Equity Method Investments - Narrative (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) investment	Feb. 28, 2014	Apr. 30, 2012 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of investments \| investment		2
Transcontinental Gas Pipe Line Company LLC
Schedule of Equity Method Investments [Line Items]
Entity's equity interest in construction agreement (as a percent)			61.00%
Constitution Pipeline Company, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)				25.00%
Contribution cap				$ 250,000,000
Other than temporary impairment	$ 95,900,000
Meade Pipeline Co LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)			20.00%
Entity's equity interest in construction agreement (as a percent)			39.00%
Expected contribution in future years		$ 75,000,000
Number of year's investment expected for contribution		2 years