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Fair Value Measurements - Schedule of Pension Plan Assets at Fair Value by Level (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | $ 2,422 | $ 2,327 |
Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 2,422 | 2,327 | $ 3,016
Pension Plan | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 1,409 | 1,265 |
Pension Plan | Total | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 340 | 335 |
Pension Plan | Total | Mutual Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 32 | 29 |
Pension Plan | Total | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 255 | 157 |
Pension Plan | Total | Corporate Bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 646 | 647 |
Pension Plan | Total | Government Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 126 | 88 |
Pension Plan | Total | Asset-backed Securities, Derivatives and Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 10 | 9 |
Pension Plan | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 627 | 521 |
Pension Plan | Level 1 | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 340 | 335 |
Pension Plan | Level 1 | Mutual Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 32 | 29 |
Pension Plan | Level 1 | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 255 | 157 |
Pension Plan | Level 1 | Corporate Bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 1 | Government Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 1 | Asset-backed Securities, Derivatives and Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 782 | 744 |
Pension Plan | Level 2 | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 2 | Mutual Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 2 | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 0 | 0 |
Pension Plan | Level 2 | Corporate Bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 646 | 647 |
Pension Plan | Level 2 | Government Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 126 | 88 |
Pension Plan | Level 2 | Asset-backed Securities, Derivatives and Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | 10 | 9 |
Pension Plan | Investments measured at net asset value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at Fair Value | $ 1,013 | $ 1,062 |

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