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Pension and Other Postretirement Benefits - Schedule of Fair Value of Pension Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net payables which represents assets related to divested businesses to be transferred to the buyers | $ 17 | $ (76) |
Pension benefits paid |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 1,531 | 1,724 | $ 4,868
Net plan assets excluding certain net receivables | 1,514 | 1,800 |
Pension benefits paid | Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 794 | 595 |
Pension benefits paid | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 608 | 431 |
Pension benefits paid | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 60 | 77 |
Pension benefits paid | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 126 | 87 |
Pension benefits paid | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 586 | 1,005 |
Pension benefits paid | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 452 | 688 |
Pension benefits paid | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 134 | 317 |
Pension benefits paid | Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 134 | 200 |
Pension benefits paid | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 64 | 83 |
Pension benefits paid | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 47 | 94 |
Pension benefits paid | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 23 | 23 |
Pension benefits paid | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 141 | 446 |
Pension benefits paid | Level 1 | Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 2 | 274 |
Pension benefits paid | Level 1 | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 2 | 274 |
Pension benefits paid | Level 1 | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 1 | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 1 | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 139 | 141 |
Pension benefits paid | Level 1 | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 124 | 78 |
Pension benefits paid | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 15 | 63 |
Pension benefits paid | Level 1 | Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 31 |
Pension benefits paid | Level 1 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 31 |
Pension benefits paid | Level 1 | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 644 | 922 |
Pension benefits paid | Level 2 | Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 197 | 89 |
Pension benefits paid | Level 2 | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 197 | 89 |
Pension benefits paid | Level 2 | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 447 | 833 |
Pension benefits paid | Level 2 | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 328 | 579 |
Pension benefits paid | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 119 | 254 |
Pension benefits paid | Level 2 | Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 729 | 432 |
Pension benefits paid | Net Asset Value | Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 595 | 232 |
Pension benefits paid | Net Asset Value | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 409 | 68 |
Pension benefits paid | Net Asset Value | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 60 | 77 |
Pension benefits paid | Net Asset Value | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 126 | 87 |
Pension benefits paid | Net Asset Value | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 31 |
Pension benefits paid | Net Asset Value | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 31 |
Pension benefits paid | Net Asset Value | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 0 | 0 |
Pension benefits paid | Net Asset Value | Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 134 | 169 |
Pension benefits paid | Net Asset Value | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 64 | 52 |
Pension benefits paid | Net Asset Value | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | 47 | 94 |
Pension benefits paid | Net Asset Value | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of pension and other postretirement plans' assets | $ 23 | $ 23 |

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