Regulatory Matters (Schedule of Net Carrying Value Of Facilities) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) MW	Dec. 31, 2017 USD ($)
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	$ 91,694	$ 86,391
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	29,245	27,876
Progress Energy [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	34,224	31,887
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	13,824	12,783
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	10,529	10,286
Duke Energy Progress [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	20,398	19,101
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Net property, plant and equipment	$ 6,643	$ 6,041
Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	865
Net property, plant and equipment	$ 283
Generation Facilities To Be Retired [Member] | Duke Energy Carolinas [Member] | Allen Steam Station Units 1-3 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	585
Net property, plant and equipment	$ 162
Generation Facilities To Be Retired [Member] | Duke Energy Indiana [Member] | Gallagher Units 2 and 4 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	280
Net property, plant and equipment	$ 121
Federal Energy Regulatory Commission [Member] | FERC 494 Refund Of Regional Transmission Enhancement Projects [Member] | Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Customer Refundable Fees, Refund Payments	$ 47