v2.4.0.8

Employee Benefit Plans (Employee Savings Plans) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
Employee Savings Plans [Abstract]
Pretax employer matching contributions	$ 30	[1]	$ 30	$ 110	[1]	$ 101
Duke Energy Carolinas [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	10	[1]	10	36	[1]	34
Progress Energy [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	10	[1]	12	33	[1]	34
Duke Energy Progress [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	7	[1]	7	23	[1]	19
Duke Energy Florida [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	3	[1]	4	10	[1]	11
Duke Energy Ohio [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions		[1]		2	[1]	2
Duke Energy Indiana [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	$ 1	[1]	$ 2	$ 5	[1]	$ 5
[1] For the three and nine months ended September 30, 2014, amounts include the additional contribution of 4 percent of eligible pay per pay period for employees not eligible to participate in a defined benefit plan.

X

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration