XML 215 R158.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Income Taxes (Effective Tax Rates) (Details) - USD ($) $ in Millions | 2 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2018 | Sep. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Oct. 31, 2016
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 645 | $ 1,493 | $ 1,307 |
State income tax, net of federal income tax effect |  |  |  |  |  | 30 | 69 | 64 |
Amortization of excess deferred income tax |  |  |  |  |  | (61) |  |  |
AFUDC equity income |  |  |  |  |  | (42) | (81) | (70) |
AFUDC equity depreciation |  |  |  |  |  | 31 |  |  |
Renewable energy production tax credits |  |  |  |  |  | (129) | (132) | (97) |
Other tax credits |  |  |  |  |  | (28) |  |  |
Tax Act |  |  |  |  |  | 20 | (112) |  |
Audit Adjustment |  |  |  |  |  |  |  | 5 |
Tax true up |  |  |  |  |  |  | (52) | (14) |
Other items, net |  |  |  |  |  | (18) | 11 | (39) |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 448 | $ 1,196 | $ 1,156 |
Effective tax rate |  |  |  |  |  | 14.60% | 28.00% | 31.00% |
Duke Energy Carolinas [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 288 | $ 653 | $ 630 |
State income tax, net of federal income tax effect |  |  |  |  |  | 14 | 36 | 46 |
AFUDC equity income |  |  |  |  |  | (15) | (37) | (36) |
AFUDC equity depreciation |  |  |  |  |  | 18 |  |  |
Other tax credits |  |  |  |  |  | (7) |  |  |
Tax Act |  |  | $ 1 |  | $ 15 | 1 | 15 |  |
Audit Adjustment |  |  |  |  |  |  |  | 3 |
Tax true up |  |  |  |  |  |  | (24) | (14) |
Other items, net |  |  |  |  |  | 4 | 9 | 5 |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 303 | $ 652 | $ 634 |
Effective tax rate |  |  |  |  |  | 22.10% | 34.90% | 35.20% |
Progress Energy [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 263 | $ 536 | $ 548 |
State income tax, net of federal income tax effect |  |  |  |  |  | 13 | 25 | 20 |
Amortization of excess deferred income tax |  |  |  |  |  | (55) |  |  |
AFUDC equity income |  |  |  |  |  | (22) | (32) | (26) |
AFUDC equity depreciation |  |  |  |  |  | 9 |  |  |
Other tax credits |  |  |  |  |  | (13) |  |  |
Tax Act |  | $ 19 | 5 | $ 1 | (246) | 25 | (246) |  |
Tax true up |  |  |  |  |  |  | (19) | (11) |
Other items, net |  |  |  |  |  | (2) |  | (4) |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 218 | $ 264 | $ 527 |
Effective tax rate |  |  |  |  |  | 17.40% | 17.20% | 33.70% |
Duke Energy Progress [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 174 | $ 353 | $ 315 |
State income tax, net of federal income tax effect |  |  |  |  |  | (17) | 8 | 10 |
Amortization of excess deferred income tax |  |  |  |  |  | (1) |  |  |
AFUDC equity income |  |  |  |  |  | (12) | (17) | (17) |
AFUDC equity depreciation |  |  |  |  |  | 5 |  |  |
Other tax credits |  |  |  |  |  | (5) |  |  |
Tax Act |  | 15 | 4 |  | (40) | 19 | (40) |  |
Tax true up |  |  |  |  |  |  | (13) | (3) |
Other items, net |  |  |  |  |  | (3) | 1 | (4) |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 160 | $ 292 | $ 301 |
Effective tax rate |  |  |  |  |  | 19.30% | 29.00% | 33.40% |
Duke Energy Florida [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 137 | $ 265 | $ 306 |
State income tax, net of federal income tax effect |  |  |  |  |  | 28 | 26 | 30 |
Amortization of excess deferred income tax |  |  |  |  |  | (54) |  |  |
AFUDC equity income |  |  |  |  |  | (10) | (16) | (9) |
AFUDC equity depreciation |  |  |  |  |  | 4 |  |  |
Other tax credits |  |  |  |  |  | (8) |  |  |
Tax Act |  | (2) | $ 2 |  | (226) |  | (226) |  |
Tax true up |  |  |  |  |  |  | (7) | (9) |
Other items, net |  |  |  |  |  | 4 | 4 | 4 |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 101 | $ 46 | $ 322 |
Effective tax rate |  |  |  |  |  | 15.40% | 6.10% | 36.90% |
Duke Energy Ohio [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 46 | $ 88 | $ 95 |
State income tax, net of federal income tax effect |  |  |  |  |  | 2 | (1) | (2) |
Amortization of excess deferred income tax |  |  |  |  |  | (3) |  |  |
AFUDC equity income |  |  |  |  |  | (2) | (4) | (2) |
AFUDC equity depreciation |  |  |  |  |  | 1 |  |  |
Other tax credits |  |  |  |  |  | (1) |  |  |
Tax Act |  | $ 2 |  |  | (23) | 2 | (23) |  |
Tax true up |  |  |  |  |  |  | (5) | (16) |
Other items, net |  |  |  |  |  | (2) | 4 | 3 |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 43 | $ 59 | $ 78 |
Effective tax rate |  |  |  |  |  | 19.60% | 23.40% | 28.90% |
Duke Energy Indiana [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate |  |  |  |  |  | $ 109 | $ 229 | $ 212 |
State income tax, net of federal income tax effect |  |  |  |  |  | 20 | 23 | 11 |
Amortization of excess deferred income tax |  |  |  |  |  | (2) |  |  |
AFUDC equity income |  |  |  |  |  | (2) | (8) | (6) |
AFUDC equity depreciation |  |  |  |  |  | 4 |  |  |
Other tax credits |  |  |  |  |  | (1) |  |  |
Tax Act |  |  |  |  | $ 55 |  | 55 |  |
Tax true up |  |  |  |  |  |  | (6) | 2 |
Other items, net |  |  |  |  |  |  | 8 | 6 |
Income tax expense (benefit) from continuing operations |  |  |  |  |  | $ 128 | $ 301 | $ 225 |
Effective tax rate |  |  |  |  |  | 24.60% | 46.00% | 37.10% |
Piedmont Natural Gas [Member] |  |  |  |  |  |  |  |  |
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract] |  |  |  |  |  |  |  |  |
Income tax expense, computed at the statutory rate | $ 30 |  |  |  |  | $ 35 | $ 70 |  | $ 111
State income tax, net of federal income tax effect | 1 |  |  |  |  | 4 | 3 |  | 11
Other tax credits |  |  |  |  |  | (3) |  |  |
Tax Act |  |  |  |  |  |  | (12) |  |
Other items, net | 1 |  |  |  |  | 1 | 1 |  | 2
Income tax expense (benefit) from continuing operations | $ 32 |  |  |  |  | $ 37 | $ 62 |  | $ 124
Effective tax rate | 37.20% |  |  |  |  | 22.30% | 30.80% |  | 39.10%

X
- Definition Effective Income Tax Rate Reconciliation, Deduction, Excess Deferred Income Tax, Amount + References No definition available. + Details
Name: | duk_EffectiveIncomeTaxRateReconciliationDeductionExcessDeferredIncomeTaxAmount
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Effective Income Tax Rate Reconciliation, Tax Credit, Renewable Energy Production + References No definition available. + Details
Name: | duk_EffectiveIncomeTaxRateReconciliationTaxCreditRenewableEnergyProduction
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Income Tax Reconciliation, Allowance For Funds Used During Construction, Equity Depreciation + References No definition available. + Details
Name: | duk_IncomeTaxReconciliationAllowanceForFundsUsedDuringConstructionEquityDepreciation
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Tax Reconciliation, Allowance For Funds Used During Construction, Equity Income + References No definition available. + Details
Name: | duk_IncomeTaxReconciliationAllowanceForFundsUsedDuringConstructionEquityIncome
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32059-109318 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other nondeductible expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationOtherAdjustments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other tax credits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxCreditsOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to domestic income tax settlement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxSettlementsDomestic
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax settlement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxSettlementsStateAndLocal
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: |