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Employee Benefit Plans - Schedule of Fair Value and Allocation of Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 1,589 | $ 1,404
Actual % of Plans' Assets | 100.00% | 100.00%
Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 763 | $ 670
Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 32 | 431
Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Fair Value Measured at Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 794 | 303
Cash and equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 31 | $ 25
Actual % of Plans' Assets | 2.00% | 2.00%
Cash and equivalents | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 0.00% | 0.00%
Cash and equivalents | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 5.00% | 5.00%
Cash and equivalents | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 31 | $ 25
Cash and equivalents | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Cash and equivalents | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0 | $ 0
Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual % of Plans' Assets | 45.00% | 46.00%
Equity securities | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 25.00% | 25.00%
Equity securities | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 65.00% | 60.00%
Common and preferred stock |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 134 | $ 88
Common and preferred stock | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 134 | 88
Common and preferred stock | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Common and preferred stock | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Mutual funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 126 | 181
Mutual funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 126 | 181
Mutual funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Mutual funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Exchange traded funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 459 | 376
Exchange traded funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 459 | 376
Exchange traded funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Exchange traded funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0 | $ 0
Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual % of Plans' Assets | 50.00% | 31.00%
Fixed income | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 30.00% | 25.00%
Fixed income | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 65.00% | 60.00%
U.S. government and government agency securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 17 | $ 198
U.S. government and government agency securities | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
U.S. government and government agency securities | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 17 | 198
U.S. government and government agency securities | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Corporate bonds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 15 | 233
Corporate bonds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Corporate bonds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 15 | 233
Corporate bonds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | $ 0
Exchange traded funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 13 |
Exchange traded funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 13 |
Exchange traded funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Exchange traded funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Collective investment funds (fixed income) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 753 |
Collective investment funds (fixed income) | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Collective investment funds (fixed income) | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Collective investment funds (fixed income) | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Collective investment funds (fixed income) | Fair Value Measured at Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 753 |
Alternative investments |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual % of Plans' Assets | 3.00% | 21.00%
Alternative investments | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 0.00% | 0.00%
Alternative investments | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted Average Target Allocation Pension Plans | 30.00% | 30.00%
Common collective trust, measured at NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | $ 302
Common collective trust, measured at NAV | Fair Value Measured at Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | 302
Limited partnerships |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 41 | 1
Limited partnerships | Fair Value Measured at Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 41 | $ 1

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