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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Jan. 01, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Maximum years of participation (in years) | 35 years |  |  |
Matching contribution (as a percent) | 100.00% |  |  |
Eligible pay (as a percent) | 6.00% |  |  |
Additional contribution for employees not participating in defined pension plans (as a percent) | 4.00% |  |  |
Vesting period (in years) | 3 years |  |  |
Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Average Earnings, Period | 3 years |  |  |
Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Average Earnings, Period | 5 years |  |  |
Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation (as a percent) | 100.00% |  |  |
Fair value of securities on loan | $ 2 | $ 390 |  |
Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 676 | (1,547) |  |
Average remaining service period (in years) | 12 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 6,267 | 6,324 |  |
Projected benefit obligation | 6,299 | 6,358 | $ 8,207 |
Benefits paid | 607 | 753 |  |
Employer contributions | $ 100 | $ 58 |  |
Expected long-term rate of return on plan assets (as a percent) | 8.25% | 6.50% | 6.50% |
Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | $ 224 |  |  |
Projected benefit obligation | 224 |  |  |
Benefits paid | 24 |  |  |
Employer contributions | $ 24 |  |  |
Pension Plan | Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected long-term rate of return on plan assets (as a percent) |  |  |  |
Pension Plan | Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Master trust allocation (as a percent) | 98.00% | 98.00% |  |
Expected long-term rate of return on plan assets (as a percent) | 7.00% |  |  |
Pension Plan | Master Trust | Liability Hedging Assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation (as a percent) |  |  |  | 35.00%
Pension Plan | Master Trust | Return Seeking Assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation (as a percent) |  |  |  | 65.00%
Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 19 | $ (31) |  |
Average remaining service period (in years) | 7 years |  |  |
Projected benefit obligation | $ 347 | 437 | $ 625 |
Benefits paid | 58 | $ 68 |  |
Employer contributions | $ 42 |  |  |
Expected long-term rate of return on plan assets (as a percent) |  | 6.50% | 6.50% |
Other Post-Retirement Benefit Plans | Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected long-term rate of return on plan assets (as a percent) | 6.50% |  |  |
Other Post-Retirement Benefit Plans | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected long-term rate of return on plan assets (as a percent) | 8.25% |  |  |
Other Post-Retirement Benefit Plans | Master Trust |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Master trust allocation (as a percent) | 2.00% | 2.00% |  |
Expected long-term rate of return on plan assets (as a percent) | 8.50% |  |  |
Target allocation (as a percent) | 100.00% |  |  |
Other Post-Retirement Benefit Plans | Master Trust | Liability Hedging Assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation (as a percent) |  |  |  | 80.00%
Other Post-Retirement Benefit Plans | Master Trust | Return Seeking Assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target allocation (as a percent) |  |  |  | 20.00%
Duke Energy Carolinas | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 183 | $ (411) |  |
Average remaining service period (in years) | 11 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 1,517 | 1,556 |  |
Projected benefit obligation | 1,514 | 1,554 | $ 1,903 |
Benefits paid | 177 | 159 |  |
Employer contributions | 26 | 15 |  |
Duke Energy Carolinas | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 10 |  |  |
Projected benefit obligation | 10 |  |  |
Benefits paid | 1 |  |  |
Employer contributions | 1 |  |  |
Duke Energy Carolinas | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 8 | (19) |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 69 | 112 | 149 |
Benefits paid | 14 | 16 |  |
Employer contributions | 6 |  |  |
Progress Energy | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 229 | (506) |  |
Average remaining service period (in years) | 14 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 1,975 | 1,959 |  |
Projected benefit obligation | 1,990 | 1,975 | 2,560 |
Benefits paid | 159 | 184 |  |
Employer contributions | 22 | 13 |  |
Progress Energy | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 78 |  |  |
Projected benefit obligation | 78 |  |  |
Benefits paid | 8 |  |  |
Employer contributions | $ 8 |  |  |
Progress Energy | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Average remaining service period (in years) | 5 years |  |  |
Projected benefit obligation | $ 146 | 168 | 263 |
Benefits paid | 22 | 26 |  |
Employer contributions | 20 |  |  |
Duke Energy Progress | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 107 | (240) |  |
Average remaining service period (in years) | 12 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 912 | 910 |  |
Projected benefit obligation | 911 | 909 | 1,153 |
Benefits paid | 80 | 101 |  |
Employer contributions | 13 | 8 |  |
Duke Energy Progress | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 23 |  |  |
Projected benefit obligation | 23 |  |  |
Benefits paid | 3 |  |  |
Employer contributions | $ 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 | $ 84 | 95 | 147 |
Benefits paid | 11 | $ 13 |  |
Employer contributions | 11 |  |  |
Duke Energy Florida |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Fair value evaluation period (in years) |  | 5 years |  |
Duke Energy Florida | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | 120 | $ (262) |  |
Accumulated Benefit Obligation at measurement date | 1,053 | 1,038 |  |
Projected benefit obligation | 1,069 | 1,055 | 1,392 |
Benefits paid | 78 | 82 |  |
Employer contributions | 9 | 5 |  |
Duke Energy Florida | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 31 |  |  |
Projected benefit obligation | 31 |  |  |
Benefits paid | 3 |  |  |
Employer contributions | $ 3 |  |  |
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 | $ 60 | 69 | 112 |
Benefits paid | 10 | 13 |  |
Employer contributions | 10 |  |  |
Duke Energy Indiana | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 45 | (107) |  |
Average remaining service period (in years) | 14 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 494 | 495 |  |
Projected benefit obligation | 496 | 499 | 680 |
Benefits paid | 40 | 66 |  |
Employer contributions | 8 | 5 |  |
Duke Energy Indiana | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 2 |  |  |
Projected benefit obligation | $ 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 | $ 24 | 30 | 54 |
Benefits paid | 6 | 8 |  |
Employer contributions | 6 |  |  |
Piedmont | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 23 | (64) |  |
Average remaining service period (in years) | 9 years |  |  |
Accumulated Benefit Obligation at measurement date | $ 176 | 170 |  |
Projected benefit obligation | 175 | 170 | 273 |
Benefits paid | 16 | 69 |  |
Employer contributions | 3 | 2 |  |
Piedmont | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 2 |  |  |
Projected benefit obligation | 2 |  |  |
Piedmont | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 4 | (7) |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 15 | 21 | 27 |
Benefits paid | 2 | 2 |  |
Employer contributions | 1 |  |  |
Duke Energy Ohio | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | 29 | (68) |  |
Accumulated Benefit Obligation at measurement date | 317 | 327 |  |
Projected benefit obligation | 325 | 333 | 450 |
Benefits paid | 31 | 50 |  |
Employer contributions | 5 | 3 |  |
Duke Energy Ohio | Pension Plan | Nonqualified Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated Benefit Obligation at measurement date | 2 |  |  |
Projected benefit obligation | 2 |  |  |
Duke Energy Ohio | Other Post-Retirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Actual return on plan assets | $ 1 | (2) |  |
Average remaining service period (in years) | 6 years |  |  |
Projected benefit obligation | $ 19 | 20 | $ 25 |
Benefits paid | 3 | 4 |  |
Employer contributions | $ 2 |  |  |
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 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Duke Energy Carolinas |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 3 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Progress Energy |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 5 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Duke Energy Progress |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 5 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Duke Energy Florida |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 1 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Piedmont |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 6 |  |
Duke Energy Retirement Cash Balance Plan | Other Nonoperating Income (Expense) | Duke Energy Ohio |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 5 |  |
Regulatory Assets, Noncurrent | Noncurrent assets |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 95 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Duke Energy Carolinas |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 35 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Progress Energy |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 23 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Duke Energy Progress |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 16 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Duke Energy Florida |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 7 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Duke Energy Indiana |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | 8 |  |
Regulatory Assets, Noncurrent | Noncurrent assets | Piedmont |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement charge |  | $ 29 |  |

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