Estimated capital cost to Duke Energy.

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- Definition

Estimated capital cost of new utility plant including AFUDC.

+ References

No definition available.

+ Details

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- Definition

MISO's estimate of Duke Energy Ohio's exit obligation to MISO

+ References

No definition available.

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- Definition

Percentage Recovered Through Future Rate Case

+ References

No definition available.

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- Definition

Percentage Recovered Through Rider

+ References

No definition available.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 10.C)

-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section C

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Regulatory Matters (Narrative) (Details) (USD $)	3 Months Ended
Regulatory Matters (Narrative) (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2017	Dec. 31, 2014
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	$ 11,279,000,000us-gaap_RegulatoryAssetsNoncurrent		$ 11,042,000,000us-gaap_RegulatoryAssetsNoncurrent
Payments to Acquire Businesses, Gross	29,000,000
Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	40.00%
Atlantic Coast Pipeline (ACP) [Member] \| Dominion Resources [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	45.00%
Sabal Trail Transmission Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	7.50%
Sabal Trail Transmission Pipeline [Member] \| Spectra Energy [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	59.50%
Sabal Trail Transmission Pipeline [Member] \| NextEra [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	33.00%
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	2,460,000,000		2,465,000,000
Duke Energy Carolinas [Member] \| William States Lee Combined Cycle Facility [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost of new utility plant, including AFUDC	600,000,000
Duke Energy Carolinas [Member] \| William States Lee Combined Cycle Facility [Member] \| NCEMC [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	13.00%
Duke Energy Progress [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	2,857,000,000		2,675,000,000
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	2,830,000,000		2,733,000,000
Duke Energy Florida [Member] \| FERC Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	10.80%
Duke Energy Florida [Member] \| FERC Complaint 3 [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	8.69%
Duke Energy Florida [Member] \| Citrus County Station [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost of new utility plant, including AFUDC	1,500,000,000
Duke Energy Florida [Member] \| Suwannee Station [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost of new utility plant, including AFUDC	197,000,000
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	512,000,000		512,000,000
Duke Energy Ohio [Member] \| FERC Complaint 1 [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	11.38%
Duke Energy Ohio [Member] \| MGP Remediation [Member] \| PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase amount by state commission	56,000,000
Duke Energy Ohio [Member] \| FERC Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	12.38%
Percentage Recovered Through Future Rate Case	30.00%
Duke Energy Ohio [Member] \| Natural Gas Rate Case [Member] \| PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	9.84%
Duke Energy Ohio [Member] \| RTO Realignment [Member]
Public Utilities, General Disclosures [Line Items]
MISO estimate of Duke Energy Ohio's MVP obligation	2,700,000,000
Duke Energy Ohio [Member] \| Regional Transmission Organization [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	73,000,000
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets, noncurrent	686,000,000		685,000,000
Duke Energy Indiana [Member] \| FERC Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	12.38%
Percentage Recovered Through Future Rate Case	0.50%
Duke Energy Indiana [Member] \| FERC Complaint 2 [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission	8.67%
Duke Energy Indiana [Member] \| Grid Infrastructure Improvement Plan [Member]
Public Utilities, General Disclosures [Line Items]
Percentage Recovered Through Rider	80.00%
Percentage Recovered Through Future Rate Case	20.00%
Estimated capital cost	1,900,000,000
Scenario, Forecast [Member] \| Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Payments to Acquire Businesses, Gross		$ 166,000,000