Commitments and Contingencies (Schedule of Environmental Loss Contingencies) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	$ 87	$ 88
Duke Energy Carolinas
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	19	19
Progress Energy
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	23	23
Duke Energy Progress
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	11	11
Duke Energy Florida
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	11	11
Duke Energy Ohio
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	33	34
Duke Energy Indiana
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	4	4
Piedmont
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	$ 8	$ 9