Variable Interest Entities (Schedule of Accounts Receivable Securitizations) (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Variable Interest Entities [Line Items]
Long-Term Debt	$ 56,049,000,000	$ 54,985,000,000
Duke Energy Carolinas
Variable Interest Entities [Line Items]
Long-Term Debt	11,497,000,000	11,142,000,000
Duke Energy Progress
Variable Interest Entities [Line Items]
Long-Term Debt	8,605,000,000	7,902,000,000
Duke Energy Florida
Variable Interest Entities [Line Items]
Long-Term Debt	7,294,000,000	7,416,000,000
CRC | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	350,000,000
Long-Term Debt	350,000,000	350,000,000
Accounts receivable from securitization	479,000,000	522,000,000
DERF | Duke Energy Carolinas | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	475,000,000
Long-Term Debt	475,000,000	474,000,000
Accounts receivable from securitization	770,000,000	642,000,000
DEPR | Duke Energy Progress | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	350,000,000
Long-Term Debt	350,000,000	325,000,000
Accounts receivable from securitization	559,000,000	489,000,000
DEFR | Duke Energy Florida | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	250,000,000
Long-Term Debt	250,000,000	250,000,000
Accounts receivable from securitization	$ 506,000,000	$ 336,000,000