Variable Interest Entities (Schedule of Accounts Receivable Securitizations) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Variable Interest Entities [Line Items]
Long-Term Debt	$ 56,311	$ 54,985
Duke Energy Carolinas
Variable Interest Entities [Line Items]
Long-Term Debt	12,050	11,142
Duke Energy Progress
Variable Interest Entities [Line Items]
Long-Term Debt	7,903	7,902
Duke Energy Florida
Variable Interest Entities [Line Items]
Long-Term Debt	7,384	7,416
CRC | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	350
Long-Term Debt	350	350
Accounts receivable from securitization	467	522
DERF | Duke Energy Carolinas | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	475
Long-Term Debt	475	474
Accounts receivable from securitization	616	642
DEPR | Duke Energy Progress | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	375
Long-Term Debt	325	325
Accounts receivable from securitization	410	489
DEFR | Duke Energy Florida | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	250
Long-Term Debt	250	250
Accounts receivable from securitization	$ 331	$ 336