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Employee Benefit Plans (Projected Benefit Obligations Reconciliation of Funded Status to Net Amount Recognized) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | $ 6,358 | $ 8,207 |
Service cost | 110 | 145 |
Interest cost | 344 | 249 |
Actuarial loss | 94 | (1,490) |
Benefits paid | (607) | (753) |
Obligation at measurement date | 6,299 | 6,358 | $ 8,207
Accumulated Benefit Obligation at measurement date | 6,267 | 6,324 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 6,993 | 9,235 |
Employer contributions | 100 | 58 |
Actual return on plan assets | 676 | (1,547) |
Benefits paid | (607) | (753) |
Plan assets at measurement date | 7,162 | 6,993 | 9,235
Funded status of plan | 863 | 635 |
Pension Plan | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Benefits paid | (24) |  |
Obligation at measurement date | 224 |  |
Accumulated Benefit Obligation at measurement date | 224 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 24 |  |
Pension Plan | Duke Energy Carolinas |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,554 | 1,903 |
Service cost | 36 | 47 |
Interest cost | 84 | 59 | 51
Actuarial loss | 11 | (301) |
Benefits paid | (177) | (159) |
Transfers | (6) | (5) |
Obligation at measurement date | 1,514 | 1,554 | 1,903
Accumulated Benefit Obligation at measurement date | 1,517 | 1,556 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 1,815 | 2,365 |
Employer contributions | 26 | 15 |
Actual return on plan assets | 183 | (411) |
Benefits paid | (177) | (159) |
Transfers | 6 | 5 |
Plan assets at measurement date | 1,853 | 1,815 | 2,365
Funded status of plan | 339 | 261 |
Pension Plan | Duke Energy Carolinas | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Benefits paid | (1) |  |
Obligation at measurement date | 10 |  |
Accumulated Benefit Obligation at measurement date | 10 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 1 |  |
Pension Plan | Progress Energy |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,975 | 2,560 |
Service cost | 30 | 40 |
Interest cost | 107 | 77 | 70
Actuarial loss | 47 | (513) |
Benefits paid | (159) | (184) |
Transfers | 10 | 5 |
Obligation at measurement date | 1,990 | 1,975 | 2,560
Accumulated Benefit Obligation at measurement date | 1,975 | 1,959 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 2,371 | 3,053 |
Employer contributions | 22 | 13 |
Actual return on plan assets | 229 | (506) |
Benefits paid | (159) | (184) |
Transfers | (10) | (5) |
Plan assets at measurement date | 2,453 | 2,371 | 3,053
Funded status of plan | 463 | 396 |
Pension Plan | Progress Energy | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Benefits paid | (8) |  |
Obligation at measurement date | 78 |  |
Accumulated Benefit Obligation at measurement date | 78 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 8 |  |
Pension Plan | Duke Energy Progress |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 909 | 1,153 |
Service cost | 18 | 24 |
Interest cost | 49 | 35 | 30
Actuarial loss | 18 | (197) |
Benefits paid | (80) | (101) |
Transfers | 3 | 5 |
Obligation at measurement date | 911 | 909 | 1,153
Accumulated Benefit Obligation at measurement date | 912 | 910 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 1,083 | 1,421 |
Employer contributions | 13 | 8 |
Actual return on plan assets | 107 | (240) |
Benefits paid | (80) | (101) |
Transfers | (3) | (5) |
Plan assets at measurement date | 1,120 | 1,083 | 1,421
Funded status of plan | 209 | 174 |
Pension Plan | Duke Energy Progress | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Benefits paid | (3) |  |
Obligation at measurement date | 23 |  |
Accumulated Benefit Obligation at measurement date | 23 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 3 |  |
Pension Plan | Duke Energy Florida |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,055 | 1,392 |
Service cost | 12 | 16 |
Interest cost | 57 | 41 | 39
Actuarial loss | 29 | (312) |
Benefits paid | (78) | (82) |
Transfers | 6 |  |
Obligation at measurement date | 1,069 | 1,055 | 1,392
Accumulated Benefit Obligation at measurement date | 1,053 | 1,038 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 1,271 | 1,610 |
Employer contributions | 9 | 5 |
Actual return on plan assets | 120 | (262) |
Benefits paid | (78) | (82) |
Transfers | (6) |  |
Plan assets at measurement date | 1,316 | 1,271 | 1,610
Funded status of plan | 247 | 216 |
Pension Plan | Duke Energy Florida | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Benefits paid | (3) |  |
Obligation at measurement date | 31 |  |
Accumulated Benefit Obligation at measurement date | 31 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 3 |  |
Pension Plan | Duke Energy Ohio |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 333 | 450 |
Service cost | 3 | 4 |
Interest cost | 18 | 13 | 13
Actuarial loss | 2 | (84) |
Benefits paid | (31) | (50) |
Obligation at measurement date | 325 | 333 | 450
Accumulated Benefit Obligation at measurement date | 317 | 327 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 323 | 438 |
Employer contributions | 5 | 3 |
Actual return on plan assets | 29 | (68) |
Benefits paid | (31) | (50) |
Plan assets at measurement date | 326 | 323 | 438
Funded status of plan | 1 | (10) |
Pension Plan | Duke Energy Ohio | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at measurement date | 2 |  |
Accumulated Benefit Obligation at measurement date | 2 |  |
Pension Plan | Duke Energy Indiana |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 499 | 680 |
Service cost | 6 | 8 |
Interest cost | 27 | 20 | 18
Actuarial loss | 4 | (143) |
Benefits paid | (40) | (66) |
Obligation at measurement date | 496 | 499 | 680
Accumulated Benefit Obligation at measurement date | 494 | 495 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 501 | 669 |
Employer contributions | 8 | 5 |
Actual return on plan assets | 45 | (107) |
Benefits paid | (40) | (66) |
Plan assets at measurement date | 514 | 501 | 669
Funded status of plan | 18 | 2 |
Pension Plan | Duke Energy Indiana | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at measurement date | 2 |  |
Accumulated Benefit Obligation at measurement date | 2 |  |
Pension Plan | Piedmont |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 170 | 273 |
Service cost | 3 | 5 |
Interest cost | 9 | 8 | 7
Actuarial loss | 9 | (47) |
Benefits paid | (16) | (69) |
Obligation at measurement date | 175 | 170 | 273
Accumulated Benefit Obligation at measurement date | 176 | 170 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 203 | 334 |
Employer contributions | 3 | 2 |
Actual return on plan assets | 23 | (64) |
Benefits paid | (16) | (69) |
Plan assets at measurement date | 213 | 203 | 334
Funded status of plan | 38 | 33 |
Pension Plan | Piedmont | Nonqualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at measurement date | 2 |  |
Accumulated Benefit Obligation at measurement date | 2 |  |
Other Post-Retirement Benefit Plans |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 437 | 625 |
Service cost | 2 | 3 | 4
Interest cost | 22 | 17 | 18
Plan participants' contributions | 4 | 11 |
Actuarial loss | (10) | (80) |
Benefits paid | (58) | (68) |
Transfers | 50 | (71) |
Obligation at measurement date | 347 | 437 | 625
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 162 | 211 |
Employer contributions | 42 |  |
Actual return on plan assets | 19 | (31) |
Benefits paid | (58) | (68) |
Transfers | (13) |  |
Plan participants' contributions | 4 | 11 |
Employer contributions |  | 39 |
Plan assets at measurement date | 156 | 162 | 211
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (191) | (275) |
Other Post-Retirement Benefit Plans | Duke Energy Carolinas |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 112 | 149 |
Service cost | 1 | 1 | 1
Interest cost | 5 | 4 | 4
Plan participants' contributions | 1 | 2 |
Actuarial loss | (2) | (17) |
Benefits paid | (14) | (16) |
Transfers | 34 | (11) |
Obligation at measurement date | 69 | 112 | 149
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 105 | 135 |
Employer contributions | 6 |  |
Actual return on plan assets | 8 | (19) |
Benefits paid | (14) | (16) |
Transfers | 4 |  |
Plan participants' contributions | 1 | 2 |
Employer contributions |  | 3 |
Plan assets at measurement date | 102 | 105 | 135
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | (8) |  |
Funded status of plan | 33 | (7) |
Other Post-Retirement Benefit Plans | Progress Energy |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 168 | 263 |
Service cost |  |  | 1
Interest cost | 9 | 7 | 7
Plan participants' contributions | 1 | 4 |
Actuarial loss | (10) | (43) |
Benefits paid | (22) | (26) |
Transfers | 0 | (37) |
Obligation at measurement date | 146 | 168 | 263
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date |  | (1) |
Employer contributions | 20 |  |
Benefits paid | (22) | (26) |
Transfers | 0 |  |
Plan participants' contributions | 1 | 4 |
Employer contributions |  | 23 |
Plan assets at measurement date | (1) |  | (1)
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (147) | (168) |
Other Post-Retirement Benefit Plans | Duke Energy Progress |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 95 | 147 |
Interest cost | 5 | 4 | 4
Plan participants' contributions | 1 | 2 |
Actuarial loss | (6) | (27) |
Benefits paid | (11) | (13) |
Transfers | 0 | (18) |
Obligation at measurement date | 84 | 95 | 147
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | (2) | (2) |
Employer contributions | 11 |  |
Benefits paid | (11) | (13) |
Transfers | 0 |  |
Plan participants' contributions | 1 | 2 |
Employer contributions |  | 11 |
Plan assets at measurement date | (1) | (2) | (2)
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (85) | (97) |
Other Post-Retirement Benefit Plans | Duke Energy Florida |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 69 | 112 |
Interest cost | 4 | 3 | 3
Plan participants' contributions | 1 | 2 |
Actuarial loss | (4) | (16) |
Benefits paid | (10) | (13) |
Transfers | 0 | (19) |
Obligation at measurement date | 60 | 69 | 112
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | (2) | (2) |
Employer contributions | 10 |  |
Benefits paid | (10) | (13) |
Transfers | 0 |  |
Plan participants' contributions | 1 | 2 |
Employer contributions |  | 11 |
Plan assets at measurement date | (1) | (2) | (2)
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (61) | (71) |
Other Post-Retirement Benefit Plans | Duke Energy Ohio |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 20 | 25 |
Interest cost | 1 | 1 | 1
Plan participants' contributions |  | 1 |
Actuarial loss | 1 | (3) |
Benefits paid | (3) | (4) |
Transfers | 0 | 0 |
Obligation at measurement date | 19 | 20 | 25
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 7 | 9 |
Employer contributions | 2 |  |
Actual return on plan assets | 1 | (2) |
Benefits paid | (3) | (4) |
Transfers | 0 |  |
Plan participants' contributions |  | 1 |
Employer contributions |  | 3 |
Plan assets at measurement date | 7 | 7 | 9
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (12) | (13) |
Other Post-Retirement Benefit Plans | Duke Energy Indiana |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 30 | 54 |
Service cost |  |  | 1
Interest cost | 1 | 1 | 1
Plan participants' contributions |  | 1 |
Actuarial loss | (1) | (1) |
Benefits paid | (6) | (8) |
Transfers | 0 | (17) |
Obligation at measurement date | 24 | 30 | 54
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 3 | 6 |
Employer contributions | 6 |  |
Benefits paid | (6) | (8) |
Transfers | 0 |  |
Plan participants' contributions |  | 1 |
Employer contributions |  | 4 |
Plan assets at measurement date | 3 | 3 | 6
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | (21) | (27) |
Other Post-Retirement Benefit Plans | Piedmont |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 21 | 27 |
Interest cost | 1 | 1 | 1
Actuarial loss | 1 | (5) |
Benefits paid | (2) | (2) |
Transfers | 6 | 0 |
Obligation at measurement date | 15 | 21 | 27
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 31 | 39 |
Employer contributions | 1 |  |
Actual return on plan assets | 4 | (7) |
Benefits paid | (2) | (2) |
Transfers | (7) |  |
Employer contributions |  | 1 |
Plan assets at measurement date | 27 | 31 | $ 39
Defined Benefit Plan, Plan Assets, 401(h) Obligation Transferred To (From) Plan | 0 |  |
Funded status of plan | $ 12 | $ 10 |

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- Definition Amount of contribution and contributions, net, received by defined benefit plan from employer which increases (decreases) plan assets. + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 60 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480266/715-60-50-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(6) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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