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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

+ Details

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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- Definition

The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520743

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520782

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(7)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Details

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- 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

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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Employee Benefit Plans (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Contribution to Qualified Pension Plan [Abstract]
Contribution to qualified pension plan			$ 27
Employee Savings Plans [Abstract]
Matching contribution percentage			100.00%
Eligible pay percentage			6.00%
Pretax employer matching contributions	30	30	101	77
Fixed-income Assets [Member]
Pension Plan Asset Allocation [Abstract]
Actual asset allocation	60.00%		60.00%
Return-seeking Assets [Member]
Pension Plan Asset Allocation [Abstract]
Actual asset allocation	40.00%		40.00%
Other Post-Retirement Benefit plans [Member]
Remeasurement [Abstract]
Plan amendments			551
Duke Energy Carolinas [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	10	8	34	28
Progress Energy [Member]
Contribution to Qualified Pension Plan [Abstract]
Contribution to qualified pension plan			27
Employee Savings Plans [Abstract]
Pretax employer matching contributions	12	12	34	35
Progress Energy [Member] \| Fixed-income Assets [Member]
Pension Plan Asset Allocation [Abstract]
Actual asset allocation	55.00%		55.00%
Progress Energy [Member] \| Return-seeking Assets [Member]
Pension Plan Asset Allocation [Abstract]
Actual asset allocation	45.00%		45.00%
Progress Energy [Member] \| Other Post-Retirement Benefit plans [Member]
Remeasurement [Abstract]
Discount rate	4.70%		4.70%
Health care cost trend rate assumed for next year			8.50%
Rate to which the cost trend is assumed to decline (the ultimate trend rate)			5.00%
Plan amendments			551
Duke Energy Progress [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	7	7	19	18
Duke Energy Progress [Member] \| Other Post-Retirement Benefit plans [Member]
Remeasurement [Abstract]
Plan amendments			382
Duke Energy Florida [Member]
Contribution to Qualified Pension Plan [Abstract]
Contribution to qualified pension plan			27
Employee Savings Plans [Abstract]
Pretax employer matching contributions	4	4	11	11
Duke Energy Florida [Member] \| Other Post-Retirement Benefit plans [Member]
Remeasurement [Abstract]
Plan amendments			103
Duke Energy Ohio [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	0	1	2	3
Duke Energy Indiana [Member]
Employee Savings Plans [Abstract]
Pretax employer matching contributions	$ 2	$ 2	$ 5	$ 5