Asset Retirement Obligations (Rollforward)(Details) (USD $) In Millions, unless otherwise specified
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12 Months Ended |
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
$ 4,958us-gaap_AssetRetirementObligation |
$ 5,176us-gaap_AssetRetirementObligation |
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Acquisitions |
4duk_AssetRetirementObligationsAcquiredFromAcquisitionOfBusiness |
4duk_AssetRetirementObligationsAcquiredFromAcquisitionOfBusiness |
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Accretion expense |
246us-gaap_AssetRetirementObligationAccretionExpense |
239us-gaap_AssetRetirementObligationAccretionExpense |
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Liabilities settled |
(68)us-gaap_AssetRetirementObligationLiabilitiesSettled |
(12)us-gaap_AssetRetirementObligationLiabilitiesSettled |
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Liabilities incurred in the current year |
3,500us-gaap_AssetRetirementObligationLiabilitiesIncurred |
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Revisions in estimates of cash flows |
(174)us-gaap_AssetRetirementObligationRevisionOfEstimate |
(449)us-gaap_AssetRetirementObligationRevisionOfEstimate |
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Balance as of December 31 |
8,466us-gaap_AssetRetirementObligation |
4,958us-gaap_AssetRetirementObligation |
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Duke Energy Carolinas [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
1,594us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
1,959us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
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Accretion expense |
113us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
122us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
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Liabilities incurred in the current year |
1,717us-gaap_AssetRetirementObligationLiabilitiesIncurred / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
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Revisions in estimates of cash flows |
4us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
(487)us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
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Balance as of December 31 |
3,428us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
1,594us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyCarolinasMember |
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Progress Energy [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
2,570us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_ProgressEnergyMember |
2,420us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_ProgressEnergyMember |
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Accretion expense |
135us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_ProgressEnergyMember |
113us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_ProgressEnergyMember |
|
Liabilities settled |
(68)us-gaap_AssetRetirementObligationLiabilitiesSettled / dei_LegalEntityAxis = duk_ProgressEnergyMember |
(12)us-gaap_AssetRetirementObligationLiabilitiesSettled / dei_LegalEntityAxis = duk_ProgressEnergyMember |
|
Liabilities incurred in the current year |
1,783us-gaap_AssetRetirementObligationLiabilitiesIncurred / dei_LegalEntityAxis = duk_ProgressEnergyMember |
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Revisions in estimates of cash flows |
291us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_ProgressEnergyMember |
49us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_ProgressEnergyMember |
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Balance as of December 31 |
4,711us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_ProgressEnergyMember |
2,570us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_ProgressEnergyMember |
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Duke Energy Progress [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
1,737us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
1,656us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
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Accretion expense |
97us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
80us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
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Liabilities incurred in the current year |
1,783us-gaap_AssetRetirementObligationLiabilitiesIncurred / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
|
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Revisions in estimates of cash flows |
288us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
1us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
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Balance as of December 31 |
3,905us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
1,737us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
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Asset retirement obligation, current |
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8us-gaap_AssetRetirementObligationCurrent / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
7us-gaap_AssetRetirementObligationCurrent / dei_LegalEntityAxis = duk_DukeEnergyProgressMember |
Duke Energy Florida [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
833us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
764us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
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Accretion expense |
38us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
33us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
|
Liabilities settled |
(68)us-gaap_AssetRetirementObligationLiabilitiesSettled / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
(12)us-gaap_AssetRetirementObligationLiabilitiesSettled / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
|
Revisions in estimates of cash flows |
3us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
48us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
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Balance as of December 31 |
806us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
833us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyFloridaMember |
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Duke Energy Ohio [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
28us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
28us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
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Accretion expense |
2us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
2us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
|
Revisions in estimates of cash flows |
(3)us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
(2)us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
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Balance as of December 31 |
27us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
28us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyOhioMember |
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Duke Energy Indiana [Member] |
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Asset Retirement Obligation [Roll Forward] |
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Balance as of January 1 |
30us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
37us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
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Accretion expense |
2us-gaap_AssetRetirementObligationAccretionExpense / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
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Revisions in estimates of cash flows |
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(7)us-gaap_AssetRetirementObligationRevisionOfEstimate / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
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Balance as of December 31 |
$ 32us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
$ 30us-gaap_AssetRetirementObligation / dei_LegalEntityAxis = duk_DukeEnergyIndianaMember |
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