The increase (decrease) in the accrual for environmental loss contingencies. These changes include remediation expense for provision of new losses and revisions in estimates of existing losses.

No definition available.

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- Definition

Estimated cost of complying with recently issued and proposed EPA Mercury and Air Toxics Standards

+ References

No definition available.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

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- Definition

The aggregate amount disbursed during the reporting period to settle environmental loss contingencies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q2)

-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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Commitments and Contingencies (Schedule of Environmental Loss Contingencies)(Details) (USD $) In Millions, unless otherwise specified	9 Months Ended							9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Minimum [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2012 Duke Energy Carolinas [Member]	Sep. 30, 2013 Duke Energy Carolinas [Member]	Dec. 31, 2012 Duke Energy Carolinas [Member]	Sep. 30, 2013 Duke Energy Carolinas [Member] Minimum [Member]	Sep. 30, 2013 Duke Energy Carolinas [Member] Maximum [Member]	Sep. 30, 2013 Duke Energy Ohio [Member]	Sep. 30, 2012 Duke Energy Ohio [Member]	Sep. 30, 2013 Duke Energy Ohio [Member] Minimum [Member]	Sep. 30, 2013 Duke Energy Ohio [Member] Maximum [Member]	Sep. 30, 2013 Duke Energy Indiana [Member]	Sep. 30, 2012 Duke Energy Indiana [Member]	Sep. 30, 2013 Duke Energy Indiana [Member] Minimum [Member]	Sep. 30, 2013 Duke Energy Indiana [Member] Maximum [Member]	Sep. 30, 2013 Progress Energy [Member]	Sep. 30, 2012 Progress Energy [Member]	Sep. 30, 2013 Progress Energy [Member] Minimum [Member]	Sep. 30, 2013 Progress Energy [Member] Maximum [Member]	Sep. 30, 2013 Duke Energy Progress [Member]	Sep. 30, 2012 Duke Energy Progress [Member]	Sep. 30, 2013 Duke Energy Progress [Member] Minimum [Member]	Sep. 30, 2013 Duke Energy Progress [Member] Maximum [Member]	Sep. 30, 2013 Duke Energy Florida [Member]	Sep. 30, 2012 Duke Energy Florida [Member]	Sep. 30, 2013 Duke Energy Florida [Member] Minimum [Member]	Sep. 30, 2013 Duke Energy Florida [Member] Maximum [Member]
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning balance	$ 75	$ 61			$ 12	$ 12	$ 12			$ 15	$ 28			$ 8	$ 9			$ 33	$ 23			$ 14	$ 11			$ 19	$ 12
Provision/adjustments	6	43			1					(1)	10			1	2			5	16			1	4			4	12
Cash reductions	(17)	(19)								(8)	(15)			(2)	(2)			(6)	(7)			(2)	(2)			(4)	(5)
Ending balance	64	85			13	12	12			6	23			7	9			32	32			13	13			19	19
Estimated cost of complying with EPA Mercury and Air Toxics Standards			$ 650	$ 800				$ 65	$ 85			$ 40	$ 85			$ 540	$ 600			$ 7	$ 30			$ 5	$ 10			$ 2	$ 20