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v3.19.3.a.u2

Pension and Other Postemployment Benefits (Details 1) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Pension |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | $ 193 | $ 224 | $ 208
Interest cost | 373 | 372 | 390
Expected return on plan assets | (540) | (574) | (448)
Amortization of prior service costs (credits) | 7 | 7 | 7
Special termination costs | 14 | 31 | 0
Pension & OPEB mark-to-market adjustment | 656 | 227 | 108
Net periodic benefit costs (credits) | 703 | 287 | 265
OPEB |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 3 | 5 | 5
Interest cost | 22 | 25 | 27
Expected return on plan assets | (29) | (31) | (30)
Amortization of prior service costs (credits) | (36) | (81) | (81)
Special termination costs | 0 | 8 | 0
Pension & OPEB mark-to-market adjustment | 20 | (82) | 13
Net periodic benefit costs (credits) | (20) | (156) | (66)
Discontinued Operations, Disposed of by Means Other than Sale | FES and FENOC | Pension |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Net periodic benefit costs (credits) | 242 | 64 | 60
Discontinued Operations, Disposed of by Means Other than Sale | FES and FENOC | OPEB |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Net periodic benefit costs (credits) | (19) | $ (25) | $ (17)
Discontinued Operations, Disposed of by Means Other than Sale | Affiliated companies | FES and FENOC | Pension Plan Enhancement |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Amounts of transaction | $ 14 |  |

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