Regulatory Matters (Narrative) (Details)				1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 03, 2017 USD ($)	Oct. 19, 2016 USD ($)	Oct. 03, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($) MW	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jan. 17, 2017 USD ($)	Jun. 30, 2016 USD ($)	Sep. 02, 2014
Public Utilities, General Disclosures [Line Items]
Net Asset Percentage Limit						25.00%
Regulatory Assets, noncurrent				$ 11,373,000,000		$ 12,878,000,000	$ 11,373,000,000
Net property, plant and equipment				73,779,000,000		82,520,000,000	73,779,000,000
Impairment charges						18,000,000	106,000,000	$ 81,000,000
Debt Instrument, Face Amount				2,700,000,000		9,127,000,000	2,700,000,000
Regulated Revenue						21,221,000,000	21,379,000,000	21,550,000,000
Regulatory assets				12,250,000,000		$ 13,901,000,000	12,250,000,000
Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						47.00%					40.00%
Long-term Purchase Commitment, Period						20 years
Sabal Trail Transmission Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						7.50%
Estimated capital cost						$ 3,200,000,000
Long-term Purchase Commitment, Period						25 years
Constitution Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						24.00%
Estimated Contributions For Pipeline And Construction Costs						$ 229,000,000
Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						9 years
Regulatory assets				2,151,000,000		$ 2,387,000,000	2,151,000,000
Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				509,000,000		534,000,000	509,000,000
NCEMPA deferrals [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				21,000,000		51,000,000	21,000,000
Nuclear asset securitized balance, net [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				1,237,000,000		1,193,000,000	1,237,000,000
Nuclear Deferral [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				245,000,000		226,000,000	245,000,000
Minimum [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						5,000,000,000
Maximum [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						5,500,000,000
Western Carolinas Modernization Plan [Member]
Public Utilities, General Disclosures [Line Items]
Approved Appeal Bond						98,000,000
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent				2,766,000,000		3,159,000,000	2,766,000,000
Net property, plant and equipment				25,877,000,000		26,762,000,000	25,877,000,000
Impairment charges						1,000,000	1,000,000	3,000,000
Debt Instrument, Face Amount				500,000,000		1,600,000,000	500,000,000
Regulatory assets				3,071,000,000		$ 3,397,000,000	3,071,000,000
Duke Energy Carolinas [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Long-term Purchase Commitment, Period						20 years
Duke Energy Carolinas [Member] | Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				479,000,000		$ 481,000,000	479,000,000
Duke Energy Carolinas [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				49,000,000		39,000,000	49,000,000
Duke Energy Carolinas [Member] | Nuclear Deferral [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				107,000,000		$ 92,000,000	107,000,000
Duke Energy Carolinas [Member] | Minimum [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						1 year
Duke Energy Carolinas [Member] | Maximum [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						6 years
Duke Energy Carolinas [Member] | FERC Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.20%
Duke Energy Carolinas [Member] | FERC Complaint [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity, Percentage						8.49%
Duke Energy Carolinas [Member] | FERC ROE Settlement [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.00%
Duke Energy Carolinas [Member] | Advanced Metering Infrastructure Deferral [Member] | PSCSC [Member] | Maximum [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent						$ 45,000,000
Duke Energy Carolinas [Member] | William States Lee Combined Cycle Facility [Member] | NCEMC [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost of new utility plant, including AFUDC						$ 600,000,000
Joint owner ownership percentage						13.00%
Duke Energy Carolinas [Member] | William State Lee III Nuclear Station [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment						$ 520,000,000
Duke Energy Progress [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent				2,710,000,000		3,243,000,000	2,710,000,000
Net property, plant and equipment				17,720,000,000		18,387,000,000	17,720,000,000
Payments to Acquire Businesses, Gross							1,249,000,000
Impairment charges						1,000,000	5,000,000	(18,000,000)
Debt Instrument, Face Amount				1,200,000,000		450,000,000	1,200,000,000
Regulatory assets				2,974,000,000		$ 3,431,000,000	2,974,000,000
Duke Energy Progress [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Long-term Purchase Commitment, Period						20 years
Duke Energy Progress [Member] | Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				366,000,000		$ 423,000,000	366,000,000
Duke Energy Progress [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						10 years
Regulatory assets				179,000,000		$ 165,000,000	179,000,000
Duke Energy Progress [Member] | NCEMPA deferrals [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						24 years
Regulatory assets				21,000,000		$ 51,000,000	21,000,000
Duke Energy Progress [Member] | Nuclear Deferral [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				62,000,000		$ 38,000,000	62,000,000
Duke Energy Progress [Member] | Maximum [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						10 years
Duke Energy Progress [Member] | FERC Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.80%
Duke Energy Progress [Member] | FERC Complaint [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity, Percentage						8.49%
Duke Energy Progress [Member] | FERC ROE Settlement [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.00%
Duke Energy Progress [Member] | Storm Cost Deferrals [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Deferred Storm and Property Reserve Deficiency, Noncurrent						$ 60,000,000
Duke Energy Progress [Member] | Storm Cost Deferrals [Member] | NCUC [Member]
Public Utilities, General Disclosures [Line Items]
Estimated Storm Costs - Capital and Operation Maintenance						$ 140,000,000
Duke Energy Progress [Member] | 2016 South Carolina Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						15 years
Duke Energy Progress [Member] | 2016 South Carolina Rate Case [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity, Percentage						10.75%
Requested Rate Increase (Decrease), Percentage						14.50%
Requested Rate Increase (Decrease), Amount						$ 79,000,000
Duke Energy Progress [Member] | 2016 South Carolina Rate Case Settlement [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission		10.10%
Approved rate increase (decrease) amount by state commission		$ 56,000,000
Duke Energy Progress [Member] | 2016 South Carolina Rate Case Settlement Year 1 Increase [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount by state commission		38,000,000
Duke Energy Progress [Member] | 2016 South Carolina Rate Case Settlement Year 2 Increase [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount by state commission		18,500,000
Duke Energy Progress [Member] | 2016 South Carolina Rate Case Settlement Year 2 Offset [Member] | PSCSC [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount by state commission		$ (18,500,000)
Duke Energy Progress [Member] | Western Carolinas Modernization Plan [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						1,100,000,000
Duke Energy Progress [Member] | FERC Mitigation [Member]
Public Utilities, General Disclosures [Line Items]
Impairment charges								(18,000,000)
Duke Energy Progress [Member] | Shearon Harris Nuclear Station [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent						48,000,000
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent				2,725,000,000		2,480,000,000	2,725,000,000
Net property, plant and equipment				10,623,000,000		11,790,000,000	10,623,000,000
Impairment charges						6,000,000	7,000,000	2,000,000
Debt Instrument, Face Amount						1,894,000,000
Regulatory assets				2,823,000,000		2,693,000,000	2,823,000,000
Duke Energy Florida [Member] | Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				441,000,000		458,000,000	441,000,000
Duke Energy Florida [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				230,000,000		257,000,000	230,000,000
Duke Energy Florida [Member] | Nuclear asset securitized balance, net [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				1,237,000,000		1,193,000,000	1,237,000,000
Duke Energy Florida [Member] | Nuclear Deferral [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				76,000,000		96,000,000	76,000,000
Duke Energy Florida [Member] | Hines Chiller Uprate Project [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						150,000,000
Duke Energy Florida [Member] | Hines Chiller Uprate Project Phase 1 [Member]
Public Utilities, General Disclosures [Line Items]
Requested Rate Increase (Decrease), Amount						17,000,000
Duke Energy Florida [Member] | Hines Chiller Uprate Project Phase 2 [Member]
Public Utilities, General Disclosures [Line Items]
Requested Rate Increase (Decrease), Amount						3,000,000
Duke Energy Florida [Member] | Osprey Energy Center Acquisition [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount by state commission						$ 48,000,000
Duke Energy Florida [Member] | 2013 FPSC Settlement Agreement [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.50%
Approved rate increase (decrease) amount by state commission						$ 150,000,000
Duke Energy Florida [Member] | 2013 FPSC Settlement Agreement [Member] | Minimum [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						9.50%
Duke Energy Florida [Member] | 2013 FPSC Settlement Agreement [Member] | Maximum [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						11.50%
Duke Energy Florida [Member] | Citrus County Station [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost of new utility plant, including AFUDC						$ 1,500,000,000
Duke Energy Florida [Member] | Crystal River Unit 3 [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						20 years
Duke Energy Florida [Member] | Crystal River Unit 3 [Member] | ISFSI Projects [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						7.35%
Regulatory Assets, noncurrent						$ 93,000,000
Duke Energy Florida [Member] | Crystal River Unit 3 [Member] | 2013 FPSC Settlement Agreement [Member] | Original Uprate Project [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						7 years
Regulatory Assets, noncurrent						$ 128,000,000
Duke Energy Florida [Member] | Crystal River Unit 3 [Member] | 2013 FPSC Settlement Agreement [Member] | FPSC [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent				1,283,000,000			1,283,000,000
Amount of Regulatory Costs Not yet Approved						1,298,000,000
Impairment charges					$ 15,000,000
Duke Energy Florida [Member] | Levy Nuclear Station [Member] | FPSC [Member]
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount by state commission						$ 0
Duke Energy Florida [Member] | Levy Nuclear Station [Member] | 2013 FPSC Settlement Agreement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						5 years
Regulatory Assets, noncurrent						$ 100,000,000
Net property, plant and equipment						119,000,000
Net unrecovered investment						$ 219,000,000
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Limit of Total Capital						30.00%
Regulatory Assets, noncurrent				497,000,000		$ 520,000,000	497,000,000
Net property, plant and equipment				5,243,000,000		5,547,000,000	5,243,000,000
Impairment charges								94,000,000
Debt Instrument, Face Amount						250,000,000
Regulated Revenue						1,410,000,000	1,331,000,000	$ 1,316,000,000
Regulatory assets				533,000,000		557,000,000	533,000,000
Duke Energy Ohio [Member] | Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				139,000,000		135,000,000	139,000,000
Duke Energy Ohio [Member] | East Bend Coal Ash Basin Filing [Member] | KPSC [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						93,000,000
Duke Energy Ohio [Member] | Natural Gas Pipeline Extension [Member] | PUCO [Member] | Minimum [Member]
Public Utilities, General Disclosures [Line Items]
Estimated Capital Cost Excluding AFUDC						86,000,000
Duke Energy Ohio [Member] | Natural Gas Pipeline Extension [Member] | PUCO [Member] | Maximum [Member]
Public Utilities, General Disclosures [Line Items]
Estimated Capital Cost Excluding AFUDC						110,000,000
Duke Energy Ohio [Member] | Accelerated Natural Gas Service Line Replacement Rider | PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Amount of Regulatory Costs Not yet Approved						240,000,000
Duke Energy Ohio [Member] | Energy Efficiency and Peak Demand Reduction Program [Member] | PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Regulated Revenue				20,000,000
Duke Energy Ohio [Member] | Mgp Remediation [Member] | PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets						99,000,000
Duke Energy Ohio [Member] | Advanced Metering Infrastructure Project [Member] | KPSC [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						49,000,000
Amount of Regulatory Costs Not yet Approved						10,000,000
Duke Energy Ohio [Member] | RTO Realignment [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				72,000,000		$ 71,000,000	72,000,000
Approved MVP Proposals						17
MISO estimate of Duke Energy Ohio's MVP obligation						$ 2,700,000,000
Duke Energy Ohio [Member] | East End Site [Member] | Mgp Remediation [Member] | PUCO [Member]
Public Utilities, General Disclosures [Line Items]
Environmental Exit Costs, Anticipated Cost						$ 46,000,000
Duke Energy Kentucky [Member]
Public Utilities, General Disclosures [Line Items]
Required Equity Capital Structure Percent						35.00%
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent				716,000,000		$ 1,073,000,000	716,000,000
Net property, plant and equipment				9,523,000,000		9,924,000,000	9,523,000,000
Impairment charges						8,000,000	88,000,000
Debt Instrument, Face Amount						500,000,000
Regulatory assets				818,000,000		1,222,000,000	818,000,000
Duke Energy Indiana [Member] | Accrued Pension And Post Retirement [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				220,000,000		222,000,000	220,000,000
Duke Energy Indiana [Member] | Retired Generation Facilities [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory assets				51,000,000		$ 73,000,000	51,000,000
Duke Energy Indiana [Member] | FERC Transmission Rates [Member] | Federal Energy Regulatory Commission [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						12.38%
Approved Return on Equity Percentage Adder						0.50%
Duke Energy Indiana [Member] | Coal Combustion Residual Plan [Member] | IURC [Member]
Public Utilities, General Disclosures [Line Items]
Requested Rate Increase (Decrease), Amount						$ 380,000,000
Federal Mandate Costs Recovered Through Tracker Mechanism						80.00%
Federally Mandated Costs Recovered In Future Rate Case						20.00%
Percentage of Costs Recovered through Existing Rider						60.00%
Percentage Recovered Through Future Rate Case						40.00%
Long-term Debt Rate						4.73%
Requested Rate Increase (Decrease), Amended, Amount						$ 365,000,000
Duke Energy Indiana [Member] | FERC Complaint 1 [Member] | Federal Energy Regulatory Commission [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.32%
Duke Energy Indiana [Member] | FERC Complaint 2 [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity, Percentage						8.67%
Duke Energy Indiana [Member] | FERC Complaint 2 [Member] | Federal Energy Regulatory Commission [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity, Percentage						9.70%
Duke Energy Indiana [Member] | Grid Infrastructure Improvement Plan [Member] | IURC [Member]
Public Utilities, General Disclosures [Line Items]
Estimated capital cost						$ 1,900,000,000
Duke Energy Indiana [Member] | Revised Grid Infrastructure Improvement Plan [Member] | IURC [Member]
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage amount by state commission						10.00%
Approved rate increase (decrease) amount by state commission						$ 1,400,000,000
Estimated capital cost						1,800,000,000
Duke Energy Indiana [Member] | Advanced Metering Infrastructure Project [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment						46,000,000
Impairment charges						$ 8,000,000
Duke Energy Indiana [Member] | Edwardsport IGCC Plant [Member] | IGCC Rider Proceeding [Member] | IURC [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Noncurrent Asset, Amortization Period						8 years
Regulatory assets						$ 161,000,000
Requested Rate Increase (Decrease), Amended, Amount						(87,500,000)
Legal Fees						$ 5,500,000
Utilities Operating Expense, Other							93,000,000
Dominion Resources [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						48.00%					45.00%
Piedmont Natural Gas [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage											10.00%
Ownership Interest in Jointly Owned Plant Transferred			3.00%
Proceeds from Divestiture of Businesses and Interests in Affiliates			$ 14,000,000
Southern Company Gas [Member] | Atlantic Coast Pipeline (ACP) [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						5.00%					5.00%
Spectra Energy [Member] | Sabal Trail Transmission Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						50.00%
NextEra [Member] | Sabal Trail Transmission Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						42.50%
Williams Partners L.P. [Member] | Constitution Pipeline [Member]
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage						41.00%
Subsequent Event [Member] | Duke Energy Florida [Member] | Osprey Energy Center Acquisition [Member]
Public Utilities, General Disclosures [Line Items]
Payments to Acquire Businesses, Gross	$ 166,000,000
Subsequent Event [Member] | Duke Energy Florida [Member] | Osprey Energy Center Acquisition [Member] | USDOJ [Member]
Public Utilities, General Disclosures [Line Items]
Other Commitment									$ 600,000
DEFPF [Member] | Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, noncurrent						$ 1,142,000,000
Debt Instrument, Face Amount						1,294,000,000
DEFPF [Member] | Duke Energy Florida [Member] | Crystal River Unit 3 [Member]
Public Utilities, General Disclosures [Line Items]
Debt Instrument, Face Amount										$ 1,294,000,000
Proceeds from Issuance of Debt						1,287,000,000
Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment						$ 424,000,000
Capacity (in MW) | MW						1,738
Generation Facilities To Be Retired [Member] | Duke Energy Progress [Member] | Asheville Plant [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment				$ 548,000,000		$ 492,000,000	$ 548,000,000
Capacity (in MW) | MW						376