Severance (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Regulatory assets	$ 14,637	$ 14,062
Duke Energy Carolinas
Restructuring Cost and Reserve [Line Items]
Regulatory assets	3,479	3,469
Duke Energy Carolinas | Employee Severance
Restructuring Cost and Reserve [Line Items]
Regulatory assets		65
Duke Energy Progress
Restructuring Cost and Reserve [Line Items]
Regulatory assets	$ 4,651	4,468
Duke Energy Progress | Employee Severance
Restructuring Cost and Reserve [Line Items]
Regulatory assets		$ 33