Equity Method Investment, Other than Temporary Impairment, Net of Tax, Portion Attributable to Parent

No definition available.

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- Definition

Equity Method Investment, Other than Temporary Impairment, Portion Attributable to Parent

+ References

No definition available.

+ Details

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- Definition

Represents the increase in number of customers.

+ References

No definition available.

+ Details

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- Definition

Represents the capacity of a natural gas pipeline.

+ References

No definition available.

+ Details

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- Definition

Represents the expansion capacity of a natural gas pipeline.

+ References

No definition available.

+ Details

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- Definition

Represents the length of a natural gas pipeline.

+ References

No definition available.

+ Details

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- Definition

Represents percentage of plant capacity.

+ 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=49116238&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=6382943&loc=d3e33918-111571

+ Details

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- Definition

Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

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- Definition

The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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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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Non-wholly Owned Entities - Narrative (Details) customer in Thousands, $ in Millions		1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 01, 2013 USD ($) customer	Dec. 31, 2013 USD ($) Bcf	Dec. 31, 2013 USD ($) Bcf	Dec. 31, 2015 USD ($) mi Bcf	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($) Bcf	Dec. 09, 2015	Sep. 30, 2014	Aug. 31, 2014
Schedule of Equity Method Investments [Line Items]
Expenditures for property, plant and equipment				$ 1,027.0	$ 769.0	$ 731.0
Distribution to noncontrolling interest				18.0	17.0	17.0
Contribution from noncontrolling interest				$ 0.0	0.0	22.0
Minimum [Member] \| Nicor Gas [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of plant capacity (as a percent)				70.00%
Maximum [Member] \| Nicor Gas [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of plant capacity (as a percent)				80.00%
South Star [Member]
Schedule of Equity Method Investments [Line Items]
Expenditures for property, plant and equipment				$ 3.0	7.0	$ 3.0
Increase in number of customers \| customer	108
Contribution from noncontrolling interest	$ 22.5
South Star [Member] \| AGL Resources Inc [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)				85.00%
South Star [Member] \| Piedmont [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)		15.00%	15.00%			15.00%	15.00%
Distribution to noncontrolling interest				$ 18.0	$ 17.0	$ 17.0
Horizon Pipeline [Member] \| Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)				50.00%
Natural gas pipeline length (in miles) \| mi				70
PennEast Pipeline [Member] \| Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)									20.00%
Natural gas pipeline length (in miles) \| mi				118
Natural gas pipeline capacity (in Bcf) \| Bcf				1.0
Natural gas pipeline expansion capacity (in Bcf) \| Bcf				1.2
Atlantic Coast Pipeline [Member] \| Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)								5.00%
Natural gas pipeline length (in miles) \| mi				564
Natural gas pipeline capacity (in Bcf) \| Bcf				1.5
Natural gas pipeline expansion capacity (in Bcf) \| Bcf				2.0
Sawgrass Storage [Member]
Schedule of Equity Method Investments [Line Items]
Impairment of equity method investment						$ 8.0
Sawgrass Storage [Member] \| Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)		50.00%	50.00%			50.00%
Natural gas pipeline capacity (in Bcf) \| Bcf		30	30			30
Impairment of equity method investment		$ 16.0
Impairment of equity method investment, portion attributable to company			$ 8.0
Impairment of equity method investment, portion attributable to company, net of tax			$ 5.0