Regulatory Matters (Schedule of Net Carrying Value Of Facilities and Megawatt Capacity) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) MW	Dec. 31, 2019 USD ($)
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	$ 105,760	$ 102,127
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	33,216	32,397
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	22,960	22,934
Duke Energy Indiana
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	$ 11,644	$ 11,072
Generation facilities to be retired
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	8,178
Public utilities, property, plant and equipment, net	$ 4,706
Generation facilities to be retired | Duke Energy Carolinas | Allen Steam Station Units 1-3
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	582
Public utilities, property, plant and equipment, net	$ 141
Generation facilities to be retired | Duke Energy Carolinas | Allen Steam Station Units 4-5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	516
Public utilities, property, plant and equipment, net	$ 321
Generation facilities to be retired | Duke Energy Carolinas | Cliffside Unit 5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	544
Public utilities, property, plant and equipment, net	$ 355
Generation facilities to be retired | Duke Energy Progress | Mayo Unit 1
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	727
Public utilities, property, plant and equipment, net	$ 673
Generation facilities to be retired | Duke Energy Progress | Roxboro Units 3-4
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	1,392
Public utilities, property, plant and equipment, net	$ 486
Generation facilities to be retired | Duke Energy Indiana | Gallagher Units 2 and 4
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	280
Public utilities, property, plant and equipment, net	$ 112
Generation facilities to be retired | Duke Energy Indiana | Gibson Units 1-5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	3,132
Public utilities, property, plant and equipment, net	$ 1,683
Generation facilities to be retired | Duke Energy Indiana | Cayuga Units 1-2
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	1,005
Public utilities, property, plant and equipment, net	$ 935