XML 110 R87.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Commitments and Contingencies (Schedule of Environmental Loss Contingencies) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | $ 77 | $ 81 | $ 98
Provision/adjustments | 33 | 26 | 8
Cash reductions | (52) | (30) | (25)
Ending balance | 58 | 77 | 81
Duke Energy Carolinas |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 11 | 10 | 10
Provision/adjustments | 6 | 3 | 3
Cash reductions | (6) | (2) | (3)
Ending balance | 11 | 11 | 10
Progress Energy |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 11 | 15 | 18
Provision/adjustments | 9 | 2 | 3
Cash reductions | (4) | (6) | (6)
Ending balance | 16 | 11 | 15
Duke Energy Progress |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 4 | 3 | 3
Provision/adjustments | 2 | 3 | 2
Cash reductions | (2) | (2) | (2)
Ending balance | 4 | 4 | 3
Duke Energy Florida |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 6 | 12 | 14
Provision/adjustments | 5 | (2) | 2
Cash reductions | (2) | (4) | (4)
Ending balance | 9 | 6 | 12
Duke Energy Ohio |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 48 | 47 | 59
Provision/adjustments | 11 | 21 | 3
Cash reductions | (40) | (20) | (15)
Ending balance | 19 | 48 | 47
Duke Energy Indiana |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 5 | 5 | 10
Provision/adjustments |  | 1 | (4)
Cash reductions | (1) | (1) | (1)
Ending balance | 4 | 5 | 5
Piedmont |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Beginning balance | 2 | 2 | 1
Provision/adjustments | 7 | 1 | 1
Cash reductions | (1) | (1) |
Ending balance | 8 | $ 2 | $ 2
Environmental reserves |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Additional losses in excess of recorded reserves that could be incurred | 59 |  |
Environmental reserves | Duke Energy Carolinas |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Additional losses in excess of recorded reserves that could be incurred | 11 |  |
Environmental reserves | Duke Energy Ohio |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Additional losses in excess of recorded reserves that could be incurred | 42 |  |
Environmental reserves | Piedmont |  |  |
Accrual for Environmental Loss Contingencies [Roll Forward] |  |  |
Additional losses in excess of recorded reserves that could be incurred | $ 2 |  |

X
- 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
Name: | duk_AmountAccruedDuringPeriodForEnvironmentalLossContingencies
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cash outflow to settle environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesPayments1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14394-108349 + Details
Name: | us-gaap_EnvironmentalExitCostsReasonablyPossibleAdditionalLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyCarolinasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_ProgressEnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyProgressMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyFloridaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyOhioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyIndianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_PiedmontNaturalGasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=duk_EnvironmentalReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |