Employee Benefit Plans (Information For Plans with Accumulated Benefit Obligation in Excess of Plan Assets) (Details) - Pension Plan - Qualified Plan - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation		$ 4,914
Accumulated benefit obligation		4,856
Fair value of plan assets		4,837
Progress Energy
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation		828
Accumulated benefit obligation		796
Fair value of plan assets		783
Duke Energy Florida
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation		828
Accumulated benefit obligation		796
Fair value of plan assets		783
Duke Energy Ohio
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	$ 153	184
Accumulated benefit obligation	143	176
Fair value of plan assets	67	96
Duke Energy Indiana
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	284	293
Accumulated benefit obligation	275	285
Fair value of plan assets	$ 173	$ 183