v3.22.0.1

Pension and Other Postretirement Benefits - Fair Value of Plan Assets (Details) - Pension benefits​ - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ 2,124 | $ 2,754 | $ 79
Plan Assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 2,128 | 2,654 |
Plan Assets | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 130 | 158 |
Plan Assets | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 412 | 602 |
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 | 1,586 | 1,894 |
Equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 652 | 527 |
Equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 12 | 1 |
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 | 640 | 526 |
Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 404 | 277 |
Equity securities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 12 | 1 |
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 | 392 | 276 |
Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 24 | 107 |
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 | 24 | 107 |
Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 224 | 143 |
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 | 224 | 143 |
Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1,192 | 1,370 |
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 | 412 | 602 |
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 | 662 | 650 |
Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1,119 | 1,325 |
Intermediate and long duration government/credit | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 95 | 117 |
Intermediate and long duration government/credit | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 412 | 602 |
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 | 612 | 606 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 73 | 45 |
Other | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 23 | 1 |
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 | 50 | 44 |
Other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 284 | 757 |
Other investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 39 |
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 | 284 | 718 |
Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 108 | 132 |
Real estate | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 39 |
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 | 108 | 93 |
Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | 531 |
Discretionary and systematic macro hedge funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | 0 |
Discretionary and systematic macro hedge funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | 0 |
Discretionary and systematic macro hedge funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | 0 |
Discretionary and systematic macro hedge funds | Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | 531 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 77 | 94 |
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 | 77 | 94 |
Net receivable |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets |  | $ 100 |
Defined Benefit Plan, Net Payable |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ (4) |  |

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