Variable Interest Entities (Sales and Cash Flows) (Details) - VIE not primary beneficiary - CRC - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Duke Energy Ohio
Variable Interest Entities [Line Items]
Receivables sold	$ 537	$ 575
Loss recognized on sale	4	4
Cash proceeds from receivables sold	559	597
Return received on retained interests	2	2
Duke Energy Indiana
Variable Interest Entities [Line Items]
Receivables sold	647	734
Loss recognized on sale	4	5
Cash proceeds from receivables sold	672	758
Return received on retained interests	$ 2	$ 3

The amount of any sales of receivables during the reporting period.

No definition available.

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719

+ Details

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- Definition

Amount of gain (loss) on sale of accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107425-111719

+ Details

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- Definition

Amount of cash inflow from collection on beneficial interest in securitization of receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

+ 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.

+ Details

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- Details

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- Details

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- Details

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- Details

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