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Investments (Net Realized Gains (Losses) on Disposals) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
HTM fixed income securities Gains | $ 0 | $ 0 | $ 1 | $ 2
HTM fixed income securities Losses | 0 | 0 | (15) | 0
Equity securities Gains | 21,630 | 10,584 | 24,868 | 20,209
Equity securities Losses | (28) | (1,919) | (135) | (2,249)
Short-term investments Gains | 2 | 3 | 18 | 6
Short-term investments Losses | (38) | (1) | (39) | (5)
Other investments Gains | 0 | 0 | 7 | 0
Other investments Losses | 0 | (5) | (30) | (5)
Net realized investment gains on disposals | 20,425 | (751) | 26,752 | 4,034
Proceeds from sale of fixed income securities, AFS | 89,700 | 444,400 | 461,825 | 1,382,677
Proceeds from sale of equity securities | 95,200 | 36,100 | 125,302 | 79,676
Fixed Maturities [Member] |  |  |  |
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
AFS securities Gains | 1,078 | 462 | 5,565 | 5,056
AFS securities Losses | $ (2,219) | $ (9,875) | $ (3,488) | $ (18,980)

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