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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Period Type:	duration

Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Debt issuances	$ 3,800,000,000
Repayments of long-term debt	2,155,000,000	$ 2,190,000,000
Parent Company [Member]
Debt Instrument [Line Items]
Debt issuances	1,800,000,000
Duke Energy Carolinas [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	3,000,000	702,000,000
Duke Energy Progress [Member]
Debt Instrument [Line Items]
Debt issuances	600,000,000
Repayments of long-term debt	602,000,000
Duke Energy Florida [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	136,000,000	635,000,000
Duke Energy Ohio [Member]
Debt Instrument [Line Items]
Debt issuances	800,000,000
Repayments of long-term debt	451,000,000	$ 3,000,000
Duke Energy Ohio [Member] \| April 2019 First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	450,000,000
Piedmont Natural Gas [Member]
Debt Instrument [Line Items]
Debt issuances	600,000,000
Repayments of long-term debt	350,000,000
Piedmont Natural Gas [Member] \| Senior Unsecured Term Loan Facility Due September 2019 [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	350,000,000
Unsecured Debt [Member] \| March 2019 Debt Issuance 3.250% Coupon Due 2022 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 300,000,000
Interest rate	3.251%
Unsecured Debt [Member] \| March 2019 Debt Issuance 3.227% Coupon Due 2022 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 300,000,000
Interest rate	3.227%
Unsecured Debt [Member] \| May 2019 Debt Issuance 3.500% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600,000,000
Interest rate	3.50%
Unsecured Debt [Member] \| June 2019 Debt Issuance 3.400% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600,000,000
Interest rate	3.40%
Unsecured Debt [Member] \| June 2019 Debt Issuance 4.200% Coupon Due 2049 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600,000,000
Interest rate	4.20%
Unsecured Debt [Member] \| Parent Company [Member] \| March 2019 Debt Issuance 3.250% Coupon Due 2022 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 300,000,000
Unsecured Debt [Member] \| Parent Company [Member] \| March 2019 Debt Issuance 3.227% Coupon Due 2022 [Member]
Debt Instrument [Line Items]
Debt issuances	300,000,000
Unsecured Debt [Member] \| Parent Company [Member] \| May 2019 Debt Issuance 3.500% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	0
Unsecured Debt [Member] \| Piedmont Natural Gas [Member] \| May 2019 Debt Issuance 3.500% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	600,000,000
First Mortgage [Member] \| January 2019 Debt Issuance 3.650% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 400,000,000
Interest rate	3.65%
First Mortgage [Member] \| January 2019 Debt Issuance 4.300% Coupon Due 2049 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 400,000,000
Interest rate	4.30%
First Mortgage [Member] \| March 2019 Debt Issuance 3.450% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600,000,000
Interest rate	3.45%
First Mortgage [Member] \| Duke Energy Progress [Member] \| March 2019 Debt Issuance 3.450% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600,000,000
First Mortgage [Member] \| Duke Energy Ohio [Member] \| January 2019 Debt Issuance 3.650% Coupon Due 2029 [Member]
Debt Instrument [Line Items]
Debt issuances	400,000,000
First Mortgage [Member] \| Duke Energy Ohio [Member] \| January 2019 Debt Issuance 4.300% Coupon Due 2049 [Member]
Debt Instrument [Line Items]
Debt issuances	$ 400,000,000