Percent of proceeds from accounts receivable securitization received as cash.

No definition available.

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- Definition

Percent of proceeds from accounts receivable securitization received as subordinated note.

+ References

No definition available.

+ Details

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- Definition

Minimum equity Balance required by Cinergy Receivables

+ References

No definition available.

+ Details

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=SL6759159-111685

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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

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=SL6759159-111685

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Variable Interest Entities (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount	$ 6,070,000,000	$ 9,127,000,000
Asset Impairment Charges	282,000,000	18,000,000	$ 106,000,000
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Financial or Other Support, Amount	$ 0	0	0
Cinergy Receivables [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Percent of proceeds received as cash	75.00%
Percent of proceeds received as subordinated note	25.00%
Minimum Equity Balance required by Cinergy Receivables	$ 3,000,000
Pioneer Transmission [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Ownership Interest	50.00%
Duke Energy Carolinas [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount	$ 550,000,000	1,600,000,000
Asset Impairment Charges		1,000,000	1,000,000
Duke Energy Progress [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount	800,000,000	450,000,000
Asset Impairment Charges	19,000,000	1,000,000	5,000,000
Duke Energy Florida [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount	1,300,000,000	1,894,000,000
Asset Impairment Charges	138,000,000	6,000,000	7,000,000
Duke Energy Florida [Member] \| DEFPF [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount				$ 1,294,000,000
Duke Energy Ohio [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount	100,000,000	250,000,000
Asset Impairment Charges	$ 1,000,000
Duke Energy Ohio [Member] \| Cinergy Receivables [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Fixed interest rate added to LIBOR to compute variable rate	1.00%
Duke Energy Ohio [Member] \| OVEC [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Ownership Interest	9.00%
Duke Energy Indiana [Member]
Variable Interest Entity [Line Items]
Debt Instrument, Face Amount		500,000,000
Asset Impairment Charges	$ 18,000,000	$ 8,000,000	$ 88,000,000
Duke Energy Indiana [Member] \| Cinergy Receivables [Member]
Variable Interest Entity [Line Items]
Fixed interest rate added to LIBOR to compute variable rate	1.00%