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.

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)

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Article 5

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

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 35

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

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+ References

No definition available.

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Investments in Unconsolidated Affiliates (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investments In Unconsolidated Affiliates [Line Items]
Gain on sale of equity investment	$ 17	$ 100	$ 22
Distributions from equity investments	154	144	183
National Methanol Company [Member] \| International Energy [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage	25.00%
Sweetwater I-V [Member] \| Commercial Power [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage	50.00%
INDU Solar Holdings [Member] \| Commercial Power [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage	50.00%
DS Cornerstone [Member] \| Commercial Power [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage	50.00%
Duke American Transmission Co. [Member] \| Commercial Power [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage	50.00%
DukeNet [Member]
Investments In Unconsolidated Affiliates [Line Items]
Net sales proceeds		215
Gain on sale of equity investment		$ 105
DukeNet [Member] \| Other [Member]
Investments In Unconsolidated Affiliates [Line Items]
Equity method investment, ownership percentage		50.00%