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Fair Value Measurements - Schedule of Pension Plan Assets at Fair Value by Level (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | $ 3,016 | $ 3,000 |
Pension Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 3,016 | 3,000 | $ 2,825
Pension Plans | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 1,893 | 2,020 |
Pension Plans | Total | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 487 | 337 |
Pension Plans | Total | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 14 | 21 |
Pension Plans | Total | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 108 | 387 |
Pension Plans | Total | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 1,013 | 1,026 |
Pension Plans | Total | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 173 | 164 |
Pension Plans | Total | Asset-backed securities, derivatives and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 98 | 85 |
Pension Plans | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 609 | 745 |
Pension Plans | Level 1 | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 487 | 337 |
Pension Plans | Level 1 | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 14 | 21 |
Pension Plans | Level 1 | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 108 | 387 |
Pension Plans | Level 1 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 1 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 1 | Asset-backed securities, derivatives and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 1,284 | 1,275 |
Pension Plans | Level 2 | Common Stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 2 | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 2 | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Pension Plans | Level 2 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 1,013 | 1,026 |
Pension Plans | Level 2 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 173 | 164 |
Pension Plans | Level 2 | Asset-backed securities, derivatives and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | 98 | 85 |
Pension Plans | Investments measured at net asset value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Investments at fair value | $ 1,123 | $ 980 |

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