The total percentage of investment held by the parent.

No definition available.

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- Details

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- Definition

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Article 5

+ Details

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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=6382943&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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- Definition

The amount of a reclassification adjustment made to prior period financial statement amounts.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

+ References

No definition available.

+ Details

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Basis of Presentation (Details) (USD $)	9 Months Ended
Basis of Presentation (Details) (USD $)	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2013 Property, plant and equipment additions, net of equity AFUDC [Member]	Sep. 30, 2013 Contributions and advances for construction costs [Member]	Sep. 30, 2014 Cardinal Pipeline Company, LLC [Member]	Dec. 31, 2013 Cardinal Pipeline Company, LLC [Member]	Sep. 30, 2014 Pine Needle LNG Company, LLC [Member]	Dec. 31, 2013 Pine Needle LNG Company, LLC [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Parent, total parent ownership percentage	66.00%
Parent, limited partner ownership percentage	64.00%
Parent, general partner ownership percentage	2.00%
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					45.00%	45.00%	35.00%	35.00%
Equity method investment, distributions	$ 6,700,000	$ 6,600,000
Equity method investment, return of capital	1,381,000	916,000
Prior Period Reclassification Adjustment [Line Items]
Prior period reclassification adjustment			$ (26,000,000)	$ 26,000,000