Represents the increase in number of customers.

No definition available.

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- Definition

Represents the capacity of a natural gas pipeline.

+ References

No definition available.

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- Definition

Represents the expansion capacity of a natural gas pipeline.

+ References

No definition available.

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- Definition

Represents the length of a natural gas pipeline.

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No definition available.

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- Definition

Represents percentage of plant capacity.

+ References

No definition available.

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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.

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-SubTopic 10

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-Subparagraph (b)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Article 5

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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.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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-Name Accounting Standards Codification

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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.

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

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Note 10 - Non-wholly Owned Entities (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2013
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Payments to Acquire Property, Plant, and Equipment	$ 769	$ 731	$ 775
Payments of Ordinary Dividends, Noncontrolling Interest	17	17	14
Proceeds from Contributions from Affiliates		22.0
Equity Method Investments	80us-gaap_EquityMethodInvestments	86us-gaap_EquityMethodInvestments			86us-gaap_EquityMethodInvestments
Proceeds from Equity Method Investment, Dividends or Distributions	17	17
South Star [Member] \| AGL Resources Inc [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage	85.00%
South Star [Member] \| Piedmont [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage		15.00%			15.00%
Payments of Ordinary Dividends, Noncontrolling Interest	17	17	14
South Star [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Payments to Acquire Property, Plant, and Equipment	7	3	1
Increase in Number of Customers				108,000
Proceeds from Contributions from Affiliates				22.5
Total Joint Venture [Member] \| Sawgrass Storage [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Other than Temporary Impairment	16
Net of Tax [Member] \| Sawgrass Storage [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Other than Temporary Impairment					5
Horizon Pipeline [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Natural Gas Pipeline Length (in Miles)	70
Equity Method Investments	14	15			15
Sawgrass Storage [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Natural Gas Pipeline Capacity (in Cubic Feet)	30,000,000,000
Equity Method Investment, Other than Temporary Impairment		8			8
PennEast Pipeline [Member] \| Corporate Joint Venture [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage	20.00%
Natural Gas Pipeline Length (in Miles)	108
Natural Gas Pipeline Capacity (in Cubic Feet)	1,000,000,000
Natural Gas Pipeline Expansion Capacity (in Cubic Feet)	1,200,000,000
PennEast Pipeline [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investments	1
Atlantic Coast Pipeline [Member] \| Corporate Joint Venture [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investment, Ownership Percentage	5.00%
Natural Gas Pipeline Length (in Miles)	550
Natural Gas Pipeline Capacity (in Cubic Feet)	1,500,000,000
Natural Gas Pipeline Expansion Capacity (in Cubic Feet)	2,000,000,000
Atlantic Coast Pipeline [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Equity Method Investments	$ 2
Minimum [Member] \| Nicor Gas [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Percentage of Plant Capacity	70.00%
Maximum [Member] \| Nicor Gas [Member]
Note 10 - Non-wholly Owned Entities (Details) [Line Items]
Percentage of Plant Capacity	80.00%