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

Jointly Owned Pipeline Proportionate Ownership Share

+ References

No definition available.

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- Definition

Purchase Agreement, Firm Transportation Capacity

+ References

No definition available.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=114001798&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

The cash outflow associated with the purchase of or advances to an 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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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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Equity Method Investments - Narrative (Details)		12 Months Ended
Equity Method Investments - Narrative (Details)	Aug. 14, 2018 USD ($) decathermal / d	Dec. 31, 2018 USD ($) investment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2018 USD ($)	Feb. 28, 2014	Apr. 30, 2012 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of investments \| investment		2
Contributions		$ 77,263,000	$ 57,039,000	$ 28,484,000
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%
Firm transportation capacity \| decathermal / d	250,000
Constitution Pipeline Company, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)							25.00%
Contribution cap							$ 250,000,000
Equity method investment, difference between carrying and underlying investment					$ 95,900,000
Contributions		500,000	4,350,000	8,975,000
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%
Contributions	$ 17,800,000	$ 76,763,000	$ 52,689,000	$ 19,509,000