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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, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pension Plan |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | $ 58 |  |
Pension Plan | Duke Energy Carolinas |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 15 |  |
Pension Plan | Progress Energy |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 13 |  |
Pension Plan | Duke Energy Progress |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 8 |  |
Pension Plan | Duke Energy Florida |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 5 |  |
Pension Plan | Duke Energy Ohio |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 3 |  |
Pension Plan | Duke Energy Indiana |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 5 |  |
Pension Plan | Piedmont |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Employer contributions | 2 |  |
Pension Plan | Qualified Plan |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 8,207 | $ 8,634 |
Service cost | 145 | 168 | $ 165
Interest cost | 249 | 220 | 269
Actuarial gain | (1,490) | (200) |
Benefits paid | (753) | (615) |
Obligation at measurement date | 6,358 | 8,207 | 8,634
Accumulated Benefit Obligation at measurement date | 6,324 | 8,144 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 9,235 | 9,337 |
Employer contributions | 58 |  |
Actual return on plan assets | (1,547) | 513 |
Benefits paid | (753) | (615) |
Plan assets at measurement date | 6,993 | 9,235 | 9,337
Funded status of plan | 635 | 1,028 |
Pension Plan | Qualified Plan | Duke Energy Carolinas |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,903 | 1,988 |
Service cost | 47 | 54 | 51
Interest cost | 59 | 51 | 62
Actuarial gain | (301) | (42) |
Benefits paid | (159) | (148) |
Transfers | 5 |  |
Obligation at measurement date | 1,554 | 1,903 | 1,988
Accumulated Benefit Obligation at measurement date | 1,556 | 1,904 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 2,365 | 2,381 |
Employer contributions | 15 |  |
Actual return on plan assets | (411) | 132 |
Benefits paid | (159) | (148) |
Transfers | 5 |  |
Plan assets at measurement date | 1,815 | 2,365 | 2,381
Funded status of plan | 261 | 462 |
Pension Plan | Qualified Plan | Progress Energy |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 2,560 | 2,715 |
Service cost | 40 | 48 | 48
Interest cost | 77 | 70 | 85
Actuarial gain | (513) | (108) |
Benefits paid | (184) | (161) |
Transfers | (5) | (4) |
Obligation at measurement date | 1,975 | 2,560 | 2,715
Accumulated Benefit Obligation at measurement date | 1,959 | 2,529 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 3,053 | 3,049 |
Employer contributions | 13 |  |
Actual return on plan assets | (506) | 169 |
Benefits paid | (184) | (161) |
Transfers | (5) | (4) |
Plan assets at measurement date | 2,371 | 3,053 | 3,049
Funded status of plan | 396 | 493 |
Pension Plan | Qualified Plan | Duke Energy Progress |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,153 | 1,193 |
Service cost | 24 | 28 | 27
Interest cost | 35 | 30 | 38
Actuarial gain | (197) | (18) |
Benefits paid | (101) | (80) |
Transfers | (5) |  |
Obligation at measurement date | 909 | 1,153 | 1,193
Accumulated Benefit Obligation at measurement date | 910 | 1,154 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 1,421 | 1,422 |
Employer contributions | 8 |  |
Actual return on plan assets | (240) | 79 |
Benefits paid | (101) | (80) |
Transfers | (5) |  |
Plan assets at measurement date | 1,083 | 1,421 | 1,422
Funded status of plan | 174 | 268 |
Pension Plan | Qualified Plan | Duke Energy Florida |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 1,392 | 1,507 |
Service cost | 16 | 20 | 21
Interest cost | 41 | 39 | 46
Actuarial gain | (312) | (89) |
Benefits paid | (82) | (81) |
Transfers |  | (4) |
Obligation at measurement date | 1,055 | 1,392 | 1,507
Accumulated Benefit Obligation at measurement date | 1,038 | 1,361 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 1,610 | 1,605 |
Employer contributions | 5 |  |
Actual return on plan assets | (262) | 90 |
Benefits paid | (82) | (81) |
Transfers |  | (4) |
Plan assets at measurement date | 1,271 | 1,610 | 1,605
Funded status of plan | 216 | 218 |
Pension Plan | Qualified Plan | Duke Energy Ohio |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 450 | 502 |
Service cost | 4 | 5 | 5
Interest cost | 13 | 13 | 15
Actuarial gain | (84) | (10) |
Benefits paid | (50) | (50) |
Transfers |  | (10) |
Obligation at measurement date | 333 | 450 | 502
Accumulated Benefit Obligation at measurement date | 327 | 439 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 438 | 472 |
Employer contributions | 3 |  |
Actual return on plan assets | (68) | 26 |
Benefits paid | (50) | (50) |
Transfers |  | (10) |
Plan assets at measurement date | 323 | 438 | 472
Funded status of plan | (10) | (12) |
Pension Plan | Qualified Plan | Duke Energy Indiana |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 680 | 715 |
Service cost | 8 | 9 | 9
Interest cost | 20 | 18 | 22
Actuarial gain | (143) | (10) |
Benefits paid | (66) | (52) |
Obligation at measurement date | 499 | 680 | 715
Accumulated Benefit Obligation at measurement date | 495 | 672 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 669 | 684 |
Employer contributions | 5 |  |
Actual return on plan assets | (107) | 37 |
Benefits paid | (66) | (52) |
Plan assets at measurement date | 501 | 669 | 684
Funded status of plan | 2 | (11) |
Pension Plan | Qualified Plan | Piedmont |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 273 | 293 |
Service cost | 5 | 6 | 6
Interest cost | 8 | 7 | 9
Actuarial gain | (47) | (5) |
Benefits paid | (69) | (28) |
Obligation at measurement date | 170 | 273 | 293
Accumulated Benefit Obligation at measurement date |  | 274 |
Accumulated Benefit Obligation at measurement date | 170 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 334 | 343 |
Employer contributions | 2 |  |
Actual return on plan assets | (64) | 19 |
Benefits paid | (69) | (28) |
Plan assets at measurement date | 203 | 334 | 343
Funded status of plan | 33 | 61 |
Other Post-Retirement Benefit Plans |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 625 | 709 |
Service cost | 3 | 4 | 4
Interest cost | 17 | 18 | 23
Plan participants' contributions | 11 | 14 |
Actuarial gain | (80) | (47) |
Plan amendments | (71) |  |
Benefits paid | (68) | (73) |
Obligation at measurement date | 437 | 625 | 709
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 211 | 237 |
Employer contributions | 39 |  |
Actual return on plan assets | (31) | 15 |
Benefits paid | (68) | (73) |
Plan participants' contributions | 11 | 14 |
Employer contributions |  | 18 |
Plan assets at measurement date | 162 | 211 | 237
Funded status of plan | (275) | (414) |
Other Post-Retirement Benefit Plans | Duke Energy Carolinas |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 149 | 174 |
Service cost | 1 | 1 | 1
Interest cost | 4 | 4 | 5
Plan participants' contributions | 2 | 3 |
Actuarial gain | (17) | (14) |
Plan amendments | (11) |  |
Benefits paid | (16) | (19) |
Obligation at measurement date | 112 | 149 | 174
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 135 | 139 |
Employer contributions | 3 |  |
Actual return on plan assets | (19) | 9 |
Benefits paid | (16) | (19) |
Plan participants' contributions | 2 | 3 |
Employer contributions |  | 3 |
Plan assets at measurement date | 105 | 135 | 139
Funded status of plan | (7) | (14) |
Other Post-Retirement Benefit Plans | Progress Energy |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 263 | 299 |
Service cost |  | 1 | 1
Interest cost | 7 | 7 | 10
Plan participants' contributions | 4 | 5 |
Actuarial gain | (43) | (20) |
Plan amendments | (37) |  |
Benefits paid | (26) | (29) |
Obligation at measurement date | 168 | 263 | 299
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | (1) | (1) |
Employer contributions | 23 |  |
Benefits paid | (26) | (29) |
Plan participants' contributions | 4 | 5 |
Employer contributions |  | 24 |
Plan assets at measurement date |  | (1) | (1)
Funded status of plan | (168) | (264) |
Other Post-Retirement Benefit Plans | Duke Energy Progress |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 147 | 166 |
Interest cost | 4 | 4 | 5
Plan participants' contributions | 2 | 3 |
Actuarial gain | (27) | (10) |
Plan amendments | (18) |  |
Benefits paid | (13) | (16) |
Obligation at measurement date | 95 | 147 | 166
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | (2) | (2) |
Employer contributions | 11 |  |
Benefits paid | (13) | (16) |
Plan participants' contributions | 2 | 3 |
Employer contributions |  | 13 |
Plan assets at measurement date | (2) | (2) | (2)
Funded status of plan | (97) | (149) |
Other Post-Retirement Benefit Plans | Duke Energy Florida |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 112 | 130 |
Interest cost | 3 | 3 | 4
Plan participants' contributions | 2 | 2 |
Actuarial gain | (16) | (10) |
Plan amendments | (19) |  |
Benefits paid | (13) | (13) |
Obligation at measurement date | 69 | 112 | 130
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | (2) | (1) |
Employer contributions | 11 |  |
Benefits paid | (13) | (13) |
Plan participants' contributions | 2 | 2 |
Employer contributions |  | 10 |
Plan assets at measurement date | (2) | (2) | (1)
Funded status of plan | (71) | (114) |
Other Post-Retirement Benefit Plans | Duke Energy Ohio |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 25 | 27 |
Interest cost | 1 | 1 | 1
Plan participants' contributions | 1 | 1 |
Actuarial gain | (3) | (1) |
Benefits paid | (4) | (3) |
Obligation at measurement date | 20 | 25 | 27
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 9 | 9 |
Employer contributions | 3 |  |
Actual return on plan assets | (2) | 1 |
Benefits paid | (4) | (3) |
Plan participants' contributions | 1 | 1 |
Employer contributions |  | 1 |
Plan assets at measurement date | 7 | 9 | 9
Funded status of plan | (13) | (16) |
Other Post-Retirement Benefit Plans | Duke Energy Indiana |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 54 | 61 |
Service cost |  | 1 | 1
Interest cost | 1 | 1 | 2
Plan participants' contributions | 1 | 2 |
Actuarial gain | (1) | (2) |
Plan amendments | (17) |  |
Benefits paid | (8) | (9) |
Obligation at measurement date | 30 | 54 | 61
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 6 | 7 |
Employer contributions | 4 |  |
Benefits paid | (8) | (9) |
Plan participants' contributions | 1 | 2 |
Employer contributions |  | 6 |
Plan assets at measurement date | 3 | 6 | 7
Funded status of plan | (27) | (48) |
Other Post-Retirement Benefit Plans | Piedmont |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |
Obligation at prior measurement date | 27 | 30 |
Interest cost | 1 | 1 | 1
Actuarial gain | (5) | (2) |
Benefits paid | (2) | (2) |
Obligation at measurement date | 21 | 27 | 30
Change in Fair Value of Plan Assets [Rollforward] |  |  |
Plan assets at prior measurement date | 39 | 37 |
Employer contributions | 1 |  |
Actual return on plan assets | (7) | 3 |
Benefits paid | (2) | (2) |
Employer contributions |  | 1 |
Plan assets at measurement date | 31 | 39 | $ 37
Funded status of plan | $ 10 | $ 12 |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 + Details
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