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Investments (Net Realized Gains (Losses) on Disposals) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |
HTM fixed income securities Gains | $ 1 | $ 0
HTM fixed income securities Losses | 0 | 0
Equity securities Gains | 0 | 2,280
Equity securities Losses | (3) | 0
Short-term investments Gains | 22 | 14
Short-term investments Losses | (190) | 0
Other investments Gains | 0 | 7
Other investments Losses | (5) | 0
Net realized investment gains on disposals | 4,100 | 3,444
Fixed Maturities [Member] |  |
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |
AFS securities Gains | 5,653 | 1,844
AFS securities Losses | $ (1,378) | $ (701)

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