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Fair Value Measurements - Proceeds from the Sale of Investments (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income |  |  |  |
Sale proceeds | $ 10 | $ 8 | $ 16 | $ 13
Realized gains | 1 | 0 | 1 | 0
Realized losses | (1) | (1) | (2) | (1)
Interest and dividend income | $ 3 | $ 2 | $ 6 | $ 5

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