Minimum Master Credit Facility Balance Required to be maintained to meet obligations outlined in Plea Agreements

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- Definition

Other Debt Matters [Abstract]

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No definition available.

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- Definition

Other Loans [Abstract]

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- Definition

Restrictive Debt Covenants [Abstract]

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No definition available.

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- Definition

Maximum amount of unsecured variable denomination floating rate demand notes available for sale.

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No definition available.

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- Definition

Maximum amount of unsecured variable denomination floating rate demand notes that can be outstanding at any point in time.

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No definition available.

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- Definition

Principal amount of unsecured variable denomination floating rate demand notes that are outstanding at the balance sheet date.

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No definition available.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

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No definition available.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of long-term loans payable classified as other.

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- Definition

The cash inflow from amounts received from a long-term debt instrument secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default.

+ References

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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- Definition

Indebtedness divided by net capital.

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No definition available.

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Debt and Credit Facilities (Narrative) (Details)	1 Months Ended	2 Months Ended	12 Months Ended
Debt and Credit Facilities (Narrative) (Details)	Jan. 31, 2019 USD ($)	Feb. 28, 2019 USD ($)	Dec. 31, 2018 USD ($)	Aug. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Debt issuances			$ 5,050,000,000		$ 6,070,000,000
Other Debt Matters [Abstract]
Demand notes, maximum amount available for sale			3,000,000,000
Demand notes, maximum amount outstanding			1,500,000,000
Principal amount of demand notes			1,010,000,000		986,000,000
Other Loans [Abstract]
Other loans outstanding against cash surrender value of life insurance policies			$ 741,000,000		701,000,000
Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 8,000,000,000
Line of credit facility, expiration date			Mar. 16, 2023
June 2017 Three Year Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 1,000,000,000.0
Debt Instrument, Term			3 years
Long-term Line of Credit			$ 500,000,000
Term Loan Proceeds			500,000,000
Duke Energy Carolinas [Member]
Debt Instrument [Line Items]
Debt issuances			$ 2,000,000,000		550,000,000
Duke Energy Carolinas [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Carolinas [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 1,750,000,000
Progress Energy [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Progress [Member]
Debt Instrument [Line Items]
Debt issuances			$ 800,000,000		800,000,000
Other Loans [Abstract]
Other loans outstanding against cash surrender value of life insurance policies			$ 37,000,000		38,000,000
Duke Energy Progress [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Progress [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 1,400,000,000
Duke Energy Progress [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 700,000,000
Debt Instrument, Term			2 years
Long-term Line of Credit			$ 50,000,000
Term Loan Proceeds			50,000,000
Duke Energy Progress [Member] \| Subsequent Event [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Drawings on credit facility		$ 650,000,000
Duke Energy Florida [Member]
Debt Instrument [Line Items]
Debt issuances			$ 1,000,000,000		1,300,000,000
Duke Energy Florida [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Florida [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 650,000,000
Duke Energy Ohio [Member]
Debt Instrument [Line Items]
Debt issuances					$ 100,000,000
Duke Energy Ohio [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Ohio [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 450,000,000
Duke Energy Indiana [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.65
Duke Energy Indiana [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 600,000,000
Piedmont Natural Gas [Member] \| Maximum [Member]
Restrictive Debt Covenants [Abstract]
Debt to total capitalization percentage, for each borrower			0.7
Piedmont Natural Gas [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility Size			$ 500,000,000
Piedmont Natural Gas [Member] \| June 2017 Piedmont Term Loan Facility [Member]
Debt Instrument [Line Items]
Facility Size			350,000,000	$ 250,000,000
Long-term Line of Credit			350,000,000
Term Loan Proceeds			350,000,000
USDOJ [Member] \| North Carolina Ash Basins [Member] \| Duke Energy Carolinas [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Minimum Master Credit Facility Balance required			250,000,000
USDOJ [Member] \| North Carolina Ash Basins [Member] \| Duke Energy Progress [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Minimum Master Credit Facility Balance required			$ 250,000,000
January 2019 First Mortgage Bonds [Member] \| Duke Energy Ohio [Member] \| Subsequent Event [Member] \| First Mortgage [Member]
Debt Instrument [Line Items]
Debt issuances	$ 800,000,000
Restrictive Debt Covenants [Abstract]
Proceeds from Issuance of First Mortgage Bond	$ 450,000,000
January 2019 First Mortgage Bonds, 3.65% Interest [Member] \| Duke Energy Ohio [Member] \| Subsequent Event [Member] \| First Mortgage [Member]
Debt Instrument [Line Items]
Interest rate	3.65%
Debt issuances	$ 400,000,000
Debt Instrument, Term	10 years
January 2019 First Mortgage Bonds, 4.30% Interest [Member] \| Duke Energy Ohio [Member] \| Subsequent Event [Member] \| First Mortgage [Member]
Debt Instrument [Line Items]
Interest rate	4.30%
Debt issuances	$ 400,000,000
Debt Instrument, Term	30 years