v2.4.0.6

Accumulated Other Comprehensive Income Changes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended											3 Months Ended												3 Months Ended								3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Accumulated Translation Adjustment [Member]	Mar. 31, 2012 Accumulated Translation Adjustment [Member]	Mar. 31, 2013 Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2012 Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2012 Accumulated Net Unrealized Investment Gain (Loss) [Member]	Mar. 31, 2013 Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2012 Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2013 Duke Energy Carolinas [Member]	Dec. 31, 2012 Duke Energy Carolinas [Member]	Mar. 31, 2013 Progress Energy [Member]	Mar. 31, 2012 Progress Energy [Member]	Mar. 31, 2013 Progress Energy [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2012 Progress Energy [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2013 Progress Energy [Member] Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2012 Progress Energy [Member] Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2013 Duke Energy Progress [Member]	Mar. 31, 2012 Duke Energy Progress [Member]	Mar. 31, 2012 Duke Energy Progress [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2012 Duke Energy Florida [Member]	Mar. 31, 2013 Duke Energy Florida [Member]	Dec. 31, 2012 Duke Energy Florida [Member]	Mar. 31, 2012 Duke Energy Florida [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Mar. 31, 2013 Duke Energy Ohio [Member]	Mar. 31, 2012 Duke Energy Ohio [Member]	Mar. 31, 2013 Duke Energy Ohio [Member] Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2012 Duke Energy Ohio [Member] Pension And OPEB Related Adjustments To AOCI [Member]	Mar. 31, 2012 Duke Energy Indiana [Member]	Mar. 31, 2013 Duke Energy Indiana [Member]	Dec. 31, 2012 Duke Energy Indiana [Member]	Mar. 31, 2012 Duke Energy Indiana [Member] Net Gains (Losses) on Cash Flow Hedges [Member]
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Accumulated other comprehensive income (loss), net of tax, beginning balance	$ (306)	$ (234)	$ (116)	$ (45)	$ (100)	$ (71)	$ (9)	$ (90)	$ (109)	$ (16)	$ (16)	$ (67)						$ 0				$ 0	$ 0		$ (1)					$ 5	$ 5
Other comprehensive income loss before reclassifications, net of tax	17	62	4	44	10	13	1	3	4
Reclassification from accumulated other comprehensive income current period, net of tax		(2)				(1)	(1)
Other comprehensive income (loss), net of tax	17	60	4	44	10	12		3	4			2	5	1	4	1	1	0	5	5	1			1	1	1	1	1	(1)			(1)
Accumulated other comprehensive income (loss), net of tax, ending balance	$ (289)	$ (174)	$ (112)	$ (1)	$ (90)	$ (59)	$ (9)	$ (87)	$ (105)	$ (16)	$ (16)	$ (65)						$ 0				$ 0	$ 0		$ 0					$ 5	$ 5

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 14, 17, 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e637-108580



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669686-108580



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e681-108580



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5



Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Net of tax amount of other comprehensive income (loss) attributable to both parent entity and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



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-Name Accounting Standards Codification

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