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Fair Value Measurements - Proceeds from the Sale of Investments (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
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 | $ 13 | $ 153
Realized gains | 4 | 7
Realized Losses | (5) | (6)
Interest and dividend income | $ 5 | $ 9

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- Definition Investment Income From Trusts + References No definition available. + Details
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- References No definition available. + Details
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