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Employee Benefits - Summary of Employer Contributions (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Company’s benefit pension plans | $ 11 | $ 12 | $ 40 | $ 62
U.K. |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Company’s benefit pension plans | 2 | 2 | 5 | 6
Other |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Company’s benefit pension plans | 2 | 2 | 10 | 10
U.S. |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Company’s benefit pension plans | $ 7 | $ 8 | $ 25 | $ 46

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