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

Reference 1: 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=6451184&loc=d3e28551-108399

Reference 2: 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=34725769&loc=d3e28878-108400

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-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

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Balance Type:	na
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- Definition

The cash outflow due to repaying amounts borrowed by issuing commercial paper.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

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Debt and Credit Facilities (Summary of Debt Issuances) (Details) (USD $)	1 Months Ended
	Apr. 30, 2015	Oct. 31, 2015	Mar. 31, 2015
Debt Instrument [Line Items]
Debt issuances			$ 500,000,000us-gaap_DebtInstrumentFaceAmount
Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of Commercial Paper	1,300,000,000
March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] \| First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Interest rate			3.75%
Debt issuances			500,000,000
March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] \| First Mortgage Bonds [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Repayments of debt		500,000,000
Duke Energy Carolinas [Member]
Debt Instrument [Line Items]
Debt issuances			500,000,000
Duke Energy Carolinas [Member] \| March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] \| First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Interest rate			3.75%
Debt issuances			500,000,000
Duke Energy Carolinas [Member] \| March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] \| First Mortgage Bonds [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Repayments of debt		$ 500,000,000