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Investments - Additional Information (Details) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021
--- | --- | --- | ---
Schedule of Investments [Line Items] |  |  |
Debt Securities, Available-for-sale, Allowance for Credit Loss | $ 1 | $ 0 | $ 0
Securities fair value | 23 | 17 |
Interest Rate Contract [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Other investments | 88 | 78 |
Reported Value Measurement [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Other investments | 92 | $ 106 |
Commitments [Member] | Partnership Interest [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Other investments | $ 70 |  |

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