Commitments and Contingencies (Narrative) (Details) T in Thousands				12 Months Ended		24 Months Ended
	Feb. 08, 2016 USD ($)	Aug. 10, 2011	Aug. 09, 2011	Dec. 31, 2015 USD ($) plant Claims project reactor	Dec. 31, 2014 USD ($)	Dec. 31, 2000 USD ($)	Aug. 18, 2014 gal	Feb. 08, 2014 T gal
Insurance [Abstract]
Insured public liability limit per nuclear incident				$ 13,500,000,000
Excess nuclear liability program coverage				13,100,000,000
Pro rata assessment for each reactor owned for each incident exceeding public liability insurance				$ 127,000,000
Number of licensed nuclear reactors | reactor				103
Annual payment limit to pro rata assessments				$ 19,000,000
Industry aggregate limit				3,200,000,000
Sublimit for non-nuclear terrorist events				$ 1,830,000,000
Insurance Coverage Percentage Initial Weeks				100.00%
Accidental Outage Insurance Coverage Initial Weeks				365 days
Insurance Coverage Percentage Additional Weeks				80.00%
Accidental Outage Insurance Coverage Additional Weeks				770 days
Weeks of Sublimits for Accidental Outage Coverage				728 days
Sublimit accidental outage recovery				$ 328,000,000
Maximum Magnitude of Retroactive Premiums				10
Maximum Period for Retroactive Premium Assessment				6 years
Valuation and Qualifying Accounts [Abstract]
Charge for settlement agreement				$ 53,000,000
Progress Energy Merger Shareholder Litigation [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement Covered by Insurance				121,000,000
Payments for Legal Settlements				25,000,000
Litigation Settlement, Amount				$ 146,000,000
Brazil Expansion Lawsuit [Member]
Valuation and Qualifying Accounts [Abstract]
Obligation to expand installed generation capacity, percent		15.00%	15.00%
North Carolina Ash Basins [Member]
Valuation and Qualifying Accounts [Abstract]
Facilities with Ash Basins | plant				14
Ash Basins Fines and Restitution [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement, Expense				$ 68,000,000
Ash Basins Community Service and Mitigation [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement, Expense				34,000,000
Antitrust Lawsuit [Member]
Valuation and Qualifying Accounts [Abstract]
Charge for settlement agreement				81,000,000
Duke Energy Carolinas [Member]
Insurance [Abstract]
Primary nuclear liability program coverage				375,000,000
Max Retroactive Premium Assessments				159,000,000
Duke Energy Carolinas [Member] | McGuire Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				1,500,000,000
Additional nuclear accident limit				1,250,000,000
Accidental outage insurance coverage policy limit				490,000,000
Duke Energy Carolinas [Member] | Catawba Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				1,500,000,000
Dedicated additional nuclear accident limit				1,250,000,000
Additional Non Nuclear Accident Limit				750,000,000
Accidental outage insurance coverage policy limit				$ 490,000,000
Potential Obligation percentage				100.00%
Duke Energy Carolinas [Member] | Oconee Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				$ 1,500,000,000
Additional nuclear accident limit				1,250,000,000
Additional Non Nuclear Accident Limit				750,000,000
Accidental outage insurance coverage policy limit				490,000,000
Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Minimum Master Credit Facility Balance required				250,000,000
Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | Dan River [Member]
Valuation and Qualifying Accounts [Abstract]
Environmental Remediation Expense					$ 24,000,000
Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | Dan River [Member] | Minimum [Member]
Valuation and Qualifying Accounts [Abstract]
Estimated amount of ash released, in tons | T								30
Estimated amount of ash basin water released, in gallons | gal								24,000,000
Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | Dan River [Member] | Maximum [Member]
Valuation and Qualifying Accounts [Abstract]
Estimated amount of ash released, in tons | T								39
Estimated amount of ash basin water released, in gallons | gal								27,000,000
Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | Operating Expense [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement, Expense					72,000,000
Duke Energy Carolinas [Member] | Groundwater Violation [Member]
Valuation and Qualifying Accounts [Abstract]
Charge for settlement agreement				$ 1,000,000
Duke Energy Carolinas [Member] | New Source Review Provisions Of Clean Air Act [Member]
Valuation and Qualifying Accounts [Abstract]
Maximum civil penalties per day for each violation						$ 37,500
Projects with Alleged NSR Violations | project				29
Number of Coal Plants with Alleged NSR Violations | plant				25
Loss contingency, pending claims, number | Claims				13
Remaining Number of Coal Units with Alleged NSR Violations | plant				13
Number of Retired Coal Plants | plant				11
Litigation Settlement, Amount				$ 4,000,000
Civil Penalty Assessed				975,000
Duke Energy Carolinas [Member] | Asbestos Issue [Member]
Valuation and Qualifying Accounts [Abstract]
Asbestos-related injuries and damages reserves				536,000,000	575,000,000
Reinsurance retention policy, excess retention, amount reinsured				847,000,000
Probable insurance recoveries				$ 599,000,000	616,000,000
Duke Energy Carolinas [Member] | Asbestos Issue [Member] | Non Malignant Asbestos Claim [Member]
Valuation and Qualifying Accounts [Abstract]
Loss contingency, pending claims, number | Claims				156
Asbestos-related injuries and damages reserves				$ 37,000,000
Duke Energy Carolinas [Member] | Asbestos Issue [Member] | Malignant Asbestos Claim [Member]
Valuation and Qualifying Accounts [Abstract]
Loss contingency, pending claims, number | Claims				70
Asbestos-related injuries and damages reserves				$ 11,000,000
Duke Energy Progress [Member]
Insurance [Abstract]
Primary nuclear liability program coverage				375,000,000
Max Retroactive Premium Assessments				108,000,000
Duke Energy Progress [Member] | Robinson Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				1,500,000,000
Additional nuclear accident limit				1,250,000,000
Accidental outage insurance coverage policy limit				457,000,000
Duke Energy Progress [Member] | Brunswick Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				1,500,000,000
Additional nuclear accident limit				1,250,000,000
Accidental outage insurance coverage policy limit				490,000,000
Duke Energy Progress [Member] | Shearon Harris Nuclear Station [Member]
Insurance [Abstract]
Sublimit property damage losses				1,500,000,000
Additional nuclear accident limit				1,250,000,000
Accidental outage insurance coverage policy limit				490,000,000
Duke Energy Progress [Member] | North Carolina Ash Basins [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Minimum Master Credit Facility Balance required				250,000,000
Duke Energy Progress [Member] | North Carolina Ash Basins [Member] | L V Sutton Plant [Member]
Valuation and Qualifying Accounts [Abstract]
Civil Penalty Assessed				25,000,000
Duke Energy Progress [Member] | North Carolina Ash Basins [Member] | Operating Expense [Member] | USDOJ [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement, Expense					30,000,000
Duke Energy Progress [Member] | Groundwater Violation [Member]
Valuation and Qualifying Accounts [Abstract]
Charge for settlement agreement				6,000,000
Duke Energy Progress [Member] | Groundwater Violation [Member] | L V Sutton Plant [Member]
Valuation and Qualifying Accounts [Abstract]
Civil Penalty Assessed				25,000,000
Duke Energy Progress [Member] | Spent Nuclear Fuels [Member]
Valuation and Qualifying Accounts [Abstract]
Gain related to litigation settlement					83,000,000
Gain contingency, unrecorded amount				48,000,000
Duke Energy Florida [Member]
Insurance [Abstract]
Primary nuclear liability program coverage				375,000,000
Max Retroactive Premium Assessments				7,000,000
Duke Energy Florida [Member] | Crystal River Unit 3 [Member]
Insurance [Abstract]
Sublimit property damage losses				$ 1,000,000,000
Potential Obligation percentage				100.00%
Duke Energy Florida [Member] | Spent Nuclear Fuels [Member]
Valuation and Qualifying Accounts [Abstract]
Gain related to litigation settlement					$ 21,000,000
Gain contingency, unrecorded amount				$ 25,000,000
Duke Energy Florida [Member] | Westinghouse Electric Company Litigation [Member]
Valuation and Qualifying Accounts [Abstract]
Gain contingency, unrecorded amount				54,000,000
Loss contingency, damages sought, value				510,000,000
Duke Energy Ohio [Member] | W.C. Beckjord Station [Member]
Valuation and Qualifying Accounts [Abstract]
Gallons of Fuel Released | gal							9,000
Duke Energy Ohio [Member] | Antitrust Lawsuit [Member]
Valuation and Qualifying Accounts [Abstract]
Litigation Settlement, Expense				81,000,000
Charge for settlement agreement				$ 81,000,000
Subsequent Event [Member] | Duke Energy Carolinas [Member] | North Carolina Ash Basins [Member] | Dan River [Member]
Valuation and Qualifying Accounts [Abstract]
Civil Penalty Assessed	$ 6,800,000