Latest year for which outstanding undesignated contracts used to hedge commodity price risk expire

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) Bcf in Millions, $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($) GWh Bcf	Dec. 31, 2015 USD ($) GWh Bcf
Derivative [Line Items]
Undesignated Commodity Contracts Latest Expiration Year		2020
Commodity Contracts [Member] \| Electricity [Member]
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours \| GWh		7	70
Commodity Contracts [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional amount, volume, in millions of decatherms \| Bcf		418	398
Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	$ 2,990	$ 2,990	$ 2,527
Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	663	663	700
Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	2,327	2,327	1,827
Variable Interest Entity, Primary Beneficiary [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	463	463	$ 497
Piedmont Natural Gas [Member]
Derivative [Line Items]
Notional amount	1,400	1,400
Piedmont Natural Gas [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	1,400	1,400
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	75	$ 168
Duke Energy Carolinas [Member] \| Commodity Contracts [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional amount, volume, in millions of decatherms \| Bcf		80	66
Duke Energy Carolinas [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	400	$ 400	$ 400
Duke Energy Carolinas [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	400	$ 400	$ 400
Progress Energy [Member] \| Commodity Contracts [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional amount, volume, in millions of decatherms \| Bcf		338	332
Progress Energy [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	500	$ 500	$ 500
Progress Energy [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	500	$ 500	$ 500
Duke Energy Progress [Member] \| Commodity Contracts [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional amount, volume, in millions of decatherms \| Bcf		124	117
Duke Energy Progress [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	250	$ 250	$ 250
Duke Energy Progress [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	250	$ 250	$ 250
Duke Energy Florida [Member] \| Commodity Contracts [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional amount, volume, in millions of decatherms \| Bcf		214	215
Duke Energy Florida [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	250	$ 250	$ 250
Duke Energy Florida [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	250	250	$ 250
Duke Energy Ohio [Member] \| Commodity Contracts [Member] \| Electricity [Member]
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours \| GWh			34
Duke Energy Ohio [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	27	27	$ 27
Duke Energy Ohio [Member] \| Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amount	$ 27	$ 27	$ 27
Duke Energy Indiana [Member] \| Commodity Contracts [Member] \| Electricity [Member]
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours \| GWh		7	36