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Employee Benefit Plans (Projected Benefit Obligations Reconciliation of Funded Status to Net Amount Recognized) (Details) - USD ($) $ in Millions | 2 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Oct. 31, 2016
Pension Plan [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | $ 141 | $ 19 | $ 155 |
Pension Plan [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 8,448 | 8,131 |  |
Service cost |  | 174 | 159 | 147 |
Interest cost |  | 299 | 328 | 335 |
Actuarial loss (gain) |  | (485) | 455 |  |
Plan amendments |  |  | (61) |  |
Benefits paid |  | (567) | (537) |  |
Impact of settlements |  |  | (27) |  |
Obligation at measurement date | $ 8,131 | 7,869 | 8,448 | 8,131 |
Accumulated benefit obligation at measurement date |  | 7,818 | 8,369 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 9,003 | 8,531 |  |
Actual return on plan assets |  | (344) | 1,017 |  |
Benefits paid |  | (567) | (537) |  |
Impact of Settlements |  |  | (27) |  |
Employer contributions |  | 141 | 19 |  |
Plan assets at measurement date | 8,531 | 8,233 | 9,003 | 8,531 |
Funded status of plan |  | 364 | 555 |  |
Pension Plan [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 331 | 332 |  |
Service cost |  | 2 | 2 | 2 |
Interest cost |  | 12 | 13 | 14 |
Actuarial loss (gain) |  | (17) | 15 |  |
Benefits paid |  | (24) | (31) |  |
Obligation at measurement date | 332 | 304 | 331 | 332 |
Accumulated benefit obligation at measurement date |  | 304 | 331 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (24) | (31) |  |
Employer contributions |  | 24 | 31 |  |
Pension Plan [Member] | Duke Energy Carolinas [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | 46 |  | 43 |
Pension Plan [Member] | Duke Energy Carolinas [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 2,029 | 1,952 |  |
Service cost |  | 56 | 48 | 48 |
Interest cost |  | 72 | 79 | 86 |
Actuarial loss (gain) |  | (44) | 68 |  |
Transfers |  |  | 27 |  |
Benefits paid |  | (159) | (145) |  |
Obligation at measurement date | 1,952 | 1,954 | 2,029 | 1,952 |
Accumulated benefit obligation at measurement date |  | 1,954 | 2,029 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 2,372 | 2,225 |  |
Actual return on plan assets |  | (91) | 265 |  |
Benefits paid |  | (159) | (145) |  |
Transfer of plan assets |  |  | 27 |  |
Employer contributions |  | 46 |  |  |
Plan assets at measurement date | 2,225 | 2,168 | 2,372 | 2,225 |
Funded status of plan |  | 214 | 343 |  |
Pension Plan [Member] | Duke Energy Carolinas [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 14 | 14 |  |
Service cost |  | 1 | 1 |  |
Interest cost |  |  | 1 | 1 |
Benefits paid |  | (1) | (2) |  |
Obligation at measurement date | 14 | 14 | 14 | 14 |
Accumulated benefit obligation at measurement date |  | 14 | 14 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (1) | (2) |  |
Employer contributions |  | 1 | 2 |  |
Pension Plan [Member] | Progress Energy [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | 45 |  | 43 |
Pension Plan [Member] | Progress Energy [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 2,637 | 2,512 |  |
Service cost |  | 49 | 45 | 42 |
Interest cost |  | 94 | 100 | 106 |
Actuarial loss (gain) |  | (204) | 158 |  |
Transfers |  |  | (32) |  |
Benefits paid |  | (143) | (146) |  |
Obligation at measurement date | 2,512 | 2,433 | 2,637 | 2,512 |
Accumulated benefit obligation at measurement date |  | 2,404 | 2,601 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 2,814 | 2,675 |  |
Actual return on plan assets |  | (110) | 317 |  |
Benefits paid |  | (143) | (146) |  |
Transfer of plan assets |  |  | (32) |  |
Employer contributions |  | 45 |  |  |
Plan assets at measurement date | 2,675 | 2,606 | 2,814 | 2,675 |
Funded status of plan |  | 173 | 177 |  |
Pension Plan [Member] | Progress Energy [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 116 | 114 |  |
Interest cost |  | 4 | 5 | 5 |
Actuarial loss (gain) |  | (6) | 5 |  |
Benefits paid |  | (8) | (8) |  |
Obligation at measurement date | 114 | 106 | 116 | 114 |
Accumulated benefit obligation at measurement date |  | 106 | 116 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (8) | (8) |  |
Employer contributions |  | 8 | 8 |  |
Pension Plan [Member] | Duke Energy Progress [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | 25 |  | 24 |
Pension Plan [Member] | Duke Energy Progress [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 1,211 | 1,158 |  |
Service cost |  | 28 | 26 | 24 |
Interest cost |  | 43 | 47 | 49 |
Actuarial loss (gain) |  | (87) | 57 |  |
Transfers |  |  | (2) |  |
Benefits paid |  | (70) | (75) |  |
Obligation at measurement date | 1,158 | 1,125 | 1,211 | 1,158 |
Accumulated benefit obligation at measurement date |  | 1,125 | 1,211 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 1,366 | 1,290 |  |
Actual return on plan assets |  | (53) | 153 |  |
Benefits paid |  | (70) | (75) |  |
Transfer of plan assets |  |  | (2) |  |
Employer contributions |  | 25 |  |  |
Plan assets at measurement date | 1,290 | 1,268 | 1,366 | 1,290 |
Funded status of plan |  | 143 | 155 |  |
Pension Plan [Member] | Duke Energy Progress [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 35 | 33 |  |
Interest cost |  | 1 | 1 | 1 |
Actuarial loss (gain) |  | (2) | 4 |  |
Benefits paid |  | (3) | (3) |  |
Obligation at measurement date | 33 | 31 | 35 | 33 |
Accumulated benefit obligation at measurement date |  | 31 | 35 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (3) | (3) |  |
Employer contributions |  | 3 | 3 |  |
Pension Plan [Member] | Duke Energy Florida [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | 20 |  | 20 |
Pension Plan [Member] | Duke Energy Florida [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 1,410 | 1,323 |  |
Service cost |  | 21 | 19 | 19 |
Interest cost |  | 50 | 53 | 55 |
Actuarial loss (gain) |  | (114) | 99 |  |
Transfers |  |  | (15) |  |
Benefits paid |  | (72) | (69) |  |
Obligation at measurement date | 1,323 | 1,295 | 1,410 | 1,323 |
Accumulated benefit obligation at measurement date |  | 1,265 | 1,375 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 1,429 | 1,352 |  |
Actual return on plan assets |  | (55) | 161 |  |
Benefits paid |  | (72) | (69) |  |
Transfer of plan assets |  |  | (15) |  |
Employer contributions |  | 20 |  |  |
Plan assets at measurement date | 1,352 | 1,322 | 1,429 | 1,352 |
Funded status of plan |  | 27 | 19 |  |
Pension Plan [Member] | Duke Energy Florida [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 47 | 46 |  |
Interest cost |  | 2 | 2 | 2 |
Actuarial loss (gain) |  | (3) | 2 |  |
Benefits paid |  | (3) | (3) |  |
Obligation at measurement date | 46 | 43 | 47 | 46 |
Accumulated benefit obligation at measurement date |  | 43 | 47 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (3) | (3) |  |
Employer contributions |  | 3 | 3 |  |
Pension Plan [Member] | Duke Energy Ohio [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  |  | 4 | 5 |
Pension Plan [Member] | Duke Energy Ohio [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 479 | 447 |  |
Service cost |  | 5 | 4 | 4 |
Interest cost |  | 17 | 18 | 19 |
Actuarial loss (gain) |  | (29) | 35 |  |
Transfers |  |  | 12 |  |
Benefits paid |  | (37) | (37) |  |
Obligation at measurement date | 447 | 435 | 479 | 447 |
Accumulated benefit obligation at measurement date |  | 425 | 468 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 458 | 428 |  |
Actual return on plan assets |  | (16) | 51 |  |
Benefits paid |  | (37) | (37) |  |
Transfer of plan assets |  |  | 12 |  |
Employer contributions |  |  | 4 |  |
Plan assets at measurement date | 428 | 405 | 458 | 428 |
Funded status of plan |  | (30) | (21) |  |
Pension Plan [Member] | Duke Energy Ohio [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 4 | 4 |  |
Actuarial loss (gain) |  | (1) |  |  |
Obligation at measurement date | 4 | 3 | 4 | 4 |
Accumulated benefit obligation at measurement date |  | 3 | 4 |  |
Pension Plan [Member] | Duke Energy Indiana [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions |  | 8 |  | 9 |
Pension Plan [Member] | Duke Energy Indiana [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 669 | 658 |  |
Service cost |  | 10 | 9 | 9 |
Interest cost |  | 23 | 26 | 28 |
Actuarial loss (gain) |  | (29) | 26 |  |
Benefits paid |  | (55) | (50) |  |
Obligation at measurement date | 658 | 618 | 669 | 658 |
Accumulated benefit obligation at measurement date |  | 614 | 652 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 684 | 657 |  |
Actual return on plan assets |  | (26) | 77 |  |
Benefits paid |  | (55) | (50) |  |
Employer contributions |  | 8 |  |  |
Plan assets at measurement date | 657 | 611 | 684 | 657 |
Funded status of plan |  | (7) | 15 |  |
Pension Plan [Member] | Duke Energy Indiana [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 3 | 3 |  |
Obligation at measurement date | 3 | 3 | 3 | 3 |
Accumulated benefit obligation at measurement date |  | 3 | 3 |  |
Pension Plan [Member] | Piedmont Natural Gas [Member] |  |  |  |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Employer contributions | 10 |  | 11 |  | $ 10
Pension Plan [Member] | Piedmont Natural Gas [Member] | Qualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 313 | 344 |  |
Service cost | 2 | 7 | 10 |  | 11
Interest cost | 2 | 11 | 14 |  | 9
Actuarial loss (gain) |  | (18) | (38) |  |
Transfers |  | (16) | 0 |  |
Plan amendments |  |  | (61) |  |
Benefits paid |  | (33) | (5) |  |
Impact of settlements |  |  | (27) |  |
Obligation at measurement date | 344 | 264 | 313 | 344 |
Accumulated benefit obligation at measurement date |  | 264 | 313 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 368 | 346 |  |
Actual return on plan assets |  | (14) | 43 |  |
Benefits paid |  | (33) | (5) |  |
Impact of Settlements |  |  | (27) |  |
Transfer of plan assets |  | (16) | 0 |  |
Employer contributions |  |  | 11 |  |
Plan assets at measurement date | 346 | 305 | 368 | 346 |
Funded status of plan |  | 41 | 55 |  |
Pension Plan [Member] | Piedmont Natural Gas [Member] | Nonqualified Plan [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 4 | 4 |  |
Service cost |  |  | 0 |  |
Interest cost |  |  | 0 |  |
Actuarial loss (gain) |  | (1) | 0 |  |
Benefits paid |  |  | 0 |  |
Obligation at measurement date | 4 | 3 | 4 | 4 |
Accumulated benefit obligation at measurement date |  | 3 | 4 |  |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  |  | 0 |  |
Employer contributions |  |  | 0 |  |
Other Post-Retirement Benefit Plans [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 813 | 868 |  |
Service cost |  | 6 | 4 | 3 |
Interest cost |  | 28 | 34 | 35 |
Plan participants' contributions |  | 18 | 17 |  |
Actuarial loss (gain) |  | (51) | 4 |  |
Plan amendments |  |  | (28) |  |
Benefits paid |  | (86) | (86) |  |
Obligation at measurement date | 868 | 728 | 813 | 868 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 225 | 244 |  |
Actual return on plan assets |  | (8) | 25 |  |
Benefits paid |  | (86) | (86) |  |
Employer contributions (reimbursements) |  |  | 25 |  |
Plan participants' contributions |  | 18 | 17 |  |
Employer contributions |  | 46 |  |  |
Plan assets at measurement date | 244 | 195 | 225 | 244 |
Funded status of plan |  | (533) | (588) |  |
Other Post-Retirement Benefit Plans [Member] | Duke Energy Carolinas [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 189 | 201 |  |
Service cost |  | 1 | 1 | 1 |
Interest cost |  | 7 | 8 | 8 |
Plan participants' contributions |  | 3 | 3 |  |
Actuarial loss (gain) |  | (8) | (3) |  |
Transfers |  |  | 2 |  |
Plan amendments |  |  | (5) |  |
Benefits paid |  | (18) | (18) |  |
Obligation at measurement date | 201 | 174 | 189 | 201 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 133 | 137 |  |
Actual return on plan assets |  | (5) | 15 |  |
Benefits paid |  | (18) | (18) |  |
Employer contributions (reimbursements) |  | 2 | (4) |  |
Plan participants' contributions |  | 3 | 3 |  |
Plan assets at measurement date | 137 | 115 | 133 | 137 |
Funded status of plan |  | (59) | (56) |  |
Other Post-Retirement Benefit Plans [Member] | Progress Energy [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 342 | 357 |  |
Service cost |  | 1 |  | 1 |
Interest cost |  | 12 | 13 | 15 |
Plan participants' contributions |  | 6 | 6 |  |
Actuarial loss (gain) |  | (23) | 4 |  |
Transfers |  |  | (1) |  |
Plan amendments |  |  | (3) |  |
Benefits paid |  | (35) | (34) |  |
Obligation at measurement date | 357 | 303 | 342 | 357 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  |  | 1 |  |
Actual return on plan assets |  |  | 1 |  |
Benefits paid |  | (35) | (34) |  |
Employer contributions (reimbursements) |  |  | 26 |  |
Plan participants' contributions |  | 6 | 6 |  |
Employer contributions |  | 29 |  |  |
Plan assets at measurement date | 1 |  |  | 1 |
Funded status of plan |  | (303) | (342) |  |
Other Post-Retirement Benefit Plans [Member] | Duke Energy Progress [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 184 | 191 |  |
Interest cost |  | 6 | 7 | 8 |
Plan participants' contributions |  | 4 | 3 |  |
Actuarial loss (gain) |  | (9) | 1 |  |
Plan amendments |  |  | (1) |  |
Benefits paid |  | (19) | (17) |  |
Obligation at measurement date | 191 | 166 | 184 | 191 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (19) | (17) |  |
Employer contributions (reimbursements) |  |  | 14 |  |
Plan participants' contributions |  | 4 | 3 |  |
Employer contributions |  | 15 |  |  |
Funded status of plan |  | (166) | (184) |  |
Other Post-Retirement Benefit Plans [Member] | Duke Energy Florida [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 156 | 164 |  |
Service cost |  | 1 |  | 1 |
Interest cost |  | 6 | 6 | 7 |
Plan participants' contributions |  | 3 | 3 |  |
Actuarial loss (gain) |  | (13) | 3 |  |
Transfers |  |  | (1) |  |
Plan amendments |  |  | (2) |  |
Benefits paid |  | (16) | (17) |  |
Obligation at measurement date | 164 | 137 | 156 | 164 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Benefits paid |  | (16) | (17) |  |
Employer contributions (reimbursements) |  |  | 14 |  |
Plan participants' contributions |  | 3 | 3 |  |
Employer contributions |  | 13 |  |  |
Funded status of plan |  | (137) | (156) |  |
Other Post-Retirement Benefit Plans [Member] | Duke Energy Ohio [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 30 | 32 |  |
Service cost |  | 1 |  |  |
Interest cost |  | 1 | 1 | 1 |
Plan participants' contributions |  | 1 | 1 |  |
Actuarial loss (gain) |  | (2) |  |  |
Transfers |  |  | 1 |  |
Plan amendments |  |  | (2) |  |
Benefits paid |  | (2) | (3) |  |
Obligation at measurement date | 32 | 29 | 30 | 32 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 7 | 7 |  |
Actual return on plan assets |  |  | 2 |  |
Benefits paid |  | (2) | (3) |  |
Plan participants' contributions |  | 1 | 1 |  |
Employer contributions |  | 2 |  |  |
Plan assets at measurement date | 7 | 8 | 7 | 7 |
Funded status of plan |  | (21) | (23) |  |
Other Post-Retirement Benefit Plans [Member] | Duke Energy Indiana [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 78 | 83 |  |
Service cost |  | 1 |  |  |
Interest cost |  | 3 | 3 | 4 |
Plan participants' contributions |  | 2 | 2 |  |
Actuarial loss (gain) |  | (5) | 3 |  |
Plan amendments |  |  | (2) |  |
Benefits paid |  | (12) | (11) |  |
Obligation at measurement date | 83 | 67 | 78 | 83 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 11 | 22 |  |
Actual return on plan assets |  |  | 1 |  |
Benefits paid |  | (12) | (11) |  |
Employer contributions (reimbursements) |  | 4 | (3) |  |
Plan participants' contributions |  | 2 | 2 |  |
Plan assets at measurement date | 22 | 5 | 11 | 22 |
Funded status of plan |  | (62) | (67) |  |
Other Post-Retirement Benefit Plans [Member] | Piedmont Natural Gas [Member] |  |  |  |  |
Change in Projected Benefit Obligation [Rollforward] |  |  |  |  |
Obligation at prior measurement date |  | 32 | 39 |  |
Service cost |  | 1 | 1 |  | 1
Interest cost |  | 1 | 1 |  | $ 1
Plan participants' contributions |  |  | 0 |  |
Actuarial loss (gain) |  | (1) | 1 |  |
Transfers |  | (1) | 0 |  |
Plan amendments |  |  | (9) |  |
Benefits paid |  | (2) | (1) |  |
Obligation at measurement date | 39 | 30 | 32 | 39 |
Change in Fair Value of Plan Assets [Rollforward] |  |  |  |  |
Plan assets at prior measurement date |  | 31 | 29 |  |
Actual return on plan assets |  | (1) | 3 |  |
Benefits paid |  | (2) | (1) |  |
Employer contributions (reimbursements) |  |  | 0 |  |
Plan participants' contributions |  |  | 0 |  |
Employer contributions |  | 1 |  |  |
Plan assets at measurement date | $ 29 | 29 | 31 | $ 29 |
Funded status of plan |  | $ (1) | $ (1) |  |

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- Definition Value of benefit obligation transferred into (out of) a defined benefit pension plan. + References No definition available. + Details
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Balance Type: | credit
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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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Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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