v2.4.0.8

Commitments and Contingencies (Schedule of Environmental Loss Contingencies) (Details) (USD $) In Millions, unless otherwise specified | 9 Months Ended
--- | ---
Sep. 30, 2014 | Sep. 30, 2013
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | $ 83 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 79 | 75
Provisions/Adjustments | 34 | 6
Cash reductions | (8) | (17)
Ending balance | 105 | 64
Duke Energy Carolinas [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 25 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 11 | 12
Provisions/Adjustments | (1) |
Cash reductions |  |
Ending balance | 10 | 12
Progress Energy [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 9 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 27 | 33
Provisions/Adjustments | 4 | 5
Cash reductions | (6) | (6)
Ending balance | 25 | 32
Duke Energy Progress [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 2 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 8 | 14
Provisions/Adjustments | 3 | 1
Cash reductions | (4) | (2)
Ending balance | 7 | 13
Duke Energy Florida [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 7 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 19 | 19
Provisions/Adjustments | 1 | 4
Cash reductions | (2) | (4)
Ending balance | 18 | 19
Duke Energy Ohio [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 42 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 27 | 15
Provisions/Adjustments | 28 | (1)
Cash reductions | (1) | (8)
Ending balance | 54 | 6
Duke Energy Indiana [Member] |  |
Environmental Matters Details [Line Items] |  |
Environmental Exit Costs, Reasonably Possible Additional Loss | 7 |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | 7 | 8
Provisions/Adjustments | 3 | 1
Cash reductions | (1) | (2)
Ending balance | $ 9 | $ 7

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- Definition The increase (decrease) in the accrual for environmental loss contingencies. These changes include remediation expense for provision of new losses and revisions in estimates of existing losses. + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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- Definition The aggregate amount disbursed during the reporting period to settle environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q2) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- Definition Estimate of reasonably possible loss exposure in excess of amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14394-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q4) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section Y -Paragraph Question 4 + Details
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