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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Jan. 01, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Maximum years of participation (in years) | 35 years |  |  |
Vesting period (in years) | 3 years |  |  |
Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 24 |  |  |
Duke Energy Retirement Cash Balance Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 117 |  |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 22 |  |  |
Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | $ 95 |  |  |
Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation | 100.00% |  |  |
Fair value of securities on loan | $ 390 | $ 542 |  |
Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 58 |  |  |
Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (1,547) | 513 |  |
Average remaining service period (in years) | 13 years |  |  |
Projected benefit obligation | $ 6,358 | 8,207 | $ 8,634 |
Accumulated Benefit Obligation at measurement date | 6,324 | 8,144 |  |
Employer contributions | 58 |  |  |
Benefits paid | $ 753 | $ 615 |  |
Expected long-term rate of return on plan assets | 6.50% | 6.50% | 6.85% |
Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | $ 232 |  |  |
Accumulated Benefit Obligation at measurement date | 232 |  |  |
Employer contributions | 24 |  |  |
Benefits paid | $ 24 |  |  |
Pension Plan | Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Master trust allocation percentage | 98.00% |  |  |
Expected long-term rate of return on plan assets | 6.50% |  |  |
Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (31) | $ 15 |  |
Average remaining service period (in years) | 7 years |  |  |
Projected benefit obligation | $ 437 | 625 | $ 709 |
Employer contributions | 39 |  |  |
Benefits paid | $ 68 | $ 73 |  |
Expected long-term rate of return on plan assets | 6.50% | 6.50% | 6.85% |
Other Post-Retirement Benefit Plans | Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Master trust allocation percentage | 2.00% |  |  |
Expected long-term rate of return on plan assets | 8.25% |  |  |
Target allocation | 100.00% |  |  |
Duke Energy Progress | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | $ 5 |  |  |
Duke Energy Progress | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 16 |  |  |
Duke Energy Progress | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 8 |  |  |
Duke Energy Progress | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (240) | $ 79 |  |
Average remaining service period (in years) | 13 years |  |  |
Projected benefit obligation | $ 909 | 1,153 | $ 1,193 |
Employer contributions | 8 |  |  |
Benefits paid | 101 | 80 |  |
Duke Energy Progress | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 24 |  |  |
Accumulated Benefit Obligation at measurement date | 24 |  |  |
Employer contributions | 3 |  |  |
Benefits paid | $ 3 |  |  |
Duke Energy Progress | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Average remaining service period (in years) | 5 years |  |  |
Projected benefit obligation | $ 95 | 147 | 166 |
Employer contributions | 11 |  |  |
Benefits paid | 13 | 16 |  |
Duke Energy Ohio | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 5 |  |  |
Duke Energy Ohio | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 3 |  |  |
Duke Energy Ohio | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (68) | 26 |  |
Average remaining service period (in years) | 15 years |  |  |
Projected benefit obligation | $ 333 | 450 | 502 |
Accumulated Benefit Obligation at measurement date | 327 | 439 |  |
Employer contributions | 3 |  |  |
Benefits paid | 50 | 50 |  |
Duke Energy Ohio | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 3 |  |  |
Accumulated Benefit Obligation at measurement date | 3 |  |  |
Duke Energy Ohio | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (2) | 1 |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 20 | 25 | 27 |
Employer contributions | 3 |  |  |
Benefits paid | 4 | 3 |  |
Progress Energy | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 5 |  |  |
Progress Energy | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 23 |  |  |
Progress Energy | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 13 |  |  |
Progress Energy | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (506) | 169 |  |
Average remaining service period (in years) | 14 years |  |  |
Projected benefit obligation | $ 1,975 | 2,560 | 2,715 |
Accumulated Benefit Obligation at measurement date | 1,959 | 2,529 |  |
Employer contributions | 13 |  |  |
Benefits paid | 184 | 161 |  |
Progress Energy | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 78 |  |  |
Accumulated Benefit Obligation at measurement date | 78 |  |  |
Employer contributions | 10 |  |  |
Benefits paid | $ 10 |  |  |
Progress Energy | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Average remaining service period (in years) | 5 years |  |  |
Projected benefit obligation | $ 168 | 263 | 299 |
Employer contributions | 23 |  |  |
Benefits paid | $ 26 | 29 |  |
Duke Energy Florida |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair value evaluation period (in years) | 5 years |  |  |
Duke Energy Florida | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | $ 1 |  |  |
Duke Energy Florida | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 7 |  |  |
Duke Energy Florida | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 5 |  |  |
Duke Energy Florida | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (262) | 90 |  |
Average remaining service period (in years) | 15 years |  |  |
Projected benefit obligation | $ 1,055 | 1,392 | 1,507 |
Accumulated Benefit Obligation at measurement date | 1,038 | 1,361 |  |
Employer contributions | 5 |  |  |
Benefits paid | 82 | 81 |  |
Duke Energy Florida | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 32 |  |  |
Accumulated Benefit Obligation at measurement date | 32 |  |  |
Employer contributions | 4 |  |  |
Benefits paid | $ 4 |  |  |
Duke Energy Florida | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Average remaining service period (in years) | 7 years |  |  |
Projected benefit obligation | $ 69 | 112 | 130 |
Employer contributions | 11 |  |  |
Benefits paid | 13 | 13 |  |
Duke Energy Carolinas | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 3 |  |  |
Duke Energy Carolinas | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 35 |  |  |
Duke Energy Carolinas | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 15 |  |  |
Duke Energy Carolinas | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (411) | 132 |  |
Average remaining service period (in years) | 12 years |  |  |
Projected benefit obligation | $ 1,554 | 1,903 | 1,988 |
Employer contributions | 15 |  |  |
Benefits paid | 159 | 148 |  |
Duke Energy Carolinas | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 10 |  |  |
Accumulated Benefit Obligation at measurement date | 10 |  |  |
Employer contributions | 1 |  |  |
Benefits paid | 1 |  |  |
Duke Energy Carolinas | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (19) | 9 |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 112 | 149 | 174 |
Employer contributions | 3 |  |  |
Benefits paid | 16 | 19 |  |
Duke Energy Indiana | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 8 |  |  |
Duke Energy Indiana | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 5 |  |  |
Duke Energy Indiana | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (107) | 37 |  |
Average remaining service period (in years) | 14 years |  |  |
Projected benefit obligation | $ 499 | 680 | 715 |
Accumulated Benefit Obligation at measurement date | 495 | 672 |  |
Employer contributions | 5 |  |  |
Benefits paid | 66 | 52 |  |
Duke Energy Indiana | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 2 |  |  |
Accumulated Benefit Obligation at measurement date | $ 2 |  |  |
Duke Energy Indiana | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 30 | 54 | 61 |
Employer contributions | 4 |  |  |
Benefits paid | $ 8 | 9 |  |
Piedmont |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Term (in years) | 3 years |  |  |
Piedmont | Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | $ 6 |  |  |
Piedmont | Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge | 29 |  |  |
Piedmont | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions | 2 |  |  |
Piedmont | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (64) | 19 |  |
Average remaining service period (in years) | 9 years |  |  |
Projected benefit obligation | $ 170 | 273 | 293 |
Accumulated Benefit Obligation at measurement date | 170 |  |  |
Employer contributions | 2 |  |  |
Benefits paid | 69 | 28 |  |
Piedmont | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Projected benefit obligation | 3 |  |  |
Accumulated Benefit Obligation at measurement date | 3 |  |  |
Piedmont | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ (7) | 3 |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 21 | 27 | $ 30 |
Employer contributions | 1 |  |  |
Benefits paid | $ 2 | $ 2 |  |
Liability Hedging Assets | Pension Plan | Master Trust | Subsequent Event |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation |  |  |  | 35.00%
Liability Hedging Assets | Other Post-Retirement Benefit Plans | Master Trust | Subsequent Event |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation |  |  |  | 80.00%
Return Seeking Assets | Pension Plan | Master Trust | Subsequent Event |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation |  |  |  | 65.00%
Return Seeking Assets | Other Post-Retirement Benefit Plans | Master Trust | Subsequent Event |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation |  |  |  | 20.00%
Minimum | Pension Plan | Qualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected long-term rate of return on plan assets |  |  |  |

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