v3.22.4

Pension and Other Postretirement Benefits - Fair Value of Plan Assets (Details) - Pension benefits​ - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ 1,383 | $ 2,124 | $ 2,754
Plan Assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1,377 | 2,128 |
Plan Assets | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 119 | 130 |
Plan Assets | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 277 | 412 |
Plan Assets | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Plan Assets | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 981 | 1,586 |
Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 300 | 652 |
Equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1 | 12 |
Equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Equities | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 299 | 640 |
Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 121 | 404 |
Equity securities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1 | 12 |
Equity securities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Equity securities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Equity securities | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 120 | 392 |
Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 23 | 24 |
Long/short equity hedge funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Long/short equity hedge funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Long/short equity hedge funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Long/short equity hedge funds | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 23 | 24 |
Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 156 | 224 |
Private equity | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Private equity | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Private equity | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Private equity | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 156 | 224 |
Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 855 | 1,192 |
Fixed income | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 118 | 118 |
Fixed income | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 277 | 412 |
Fixed income | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Fixed income | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 460 | 662 |
Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 759 | 1,119 |
Intermediate and long duration government/credit | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 113 | 95 |
Intermediate and long duration government/credit | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 277 | 412 |
Intermediate and long duration government/credit | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Intermediate and long duration government/credit | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 369 | 612 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 96 | 73 |
Other | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 5 | 23 |
Other | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 91 | 50 |
Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 222 | 284 |
Other investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other investments | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other investments | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 222 | 284 |
Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 93 | 108 |
Real estate | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Real estate | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Real estate | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Real estate | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 93 | 108 |
Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 100 | 99 |
Discretionary and systematic macro hedge funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Discretionary and systematic macro hedge funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Discretionary and systematic macro hedge funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Discretionary and systematic macro hedge funds | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 100 | 99 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 29 | 77 |
Other | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
Other | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 29 | 77 |
Net receivable |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ 7 |  |
Defined Benefit Plan, Net Payable |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | $ (4) |

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