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v3.19.1

Fair Value Measurements (Details 4) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
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 | $ 153 | $ 191
Realized Gains | 7 | 19
Realized Losses | (6) | (16)
Interest and Dividend Income | $ 9 | $ 10

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