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Investments (Net Realized Gains (Losses) on Disposals) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
HTM fixed income securities Gains | $ 1 | $ 0 | $ 1 | $ 2
HTM fixed income securities Losses | (15) | 0 | (15) | 0
Equity securities Gains | 958 | 1,226 | 3,238 | 9,625
Equity securities Losses | (107) | 0 | (107) | (330)
Short-term investments Gains | 2 | 2 | 16 | 3
Short-term investments Losses | (1) | 0 | (1) | (4)
Other investments Gains | 0 | 0 | 7 | 0
Other investments Losses | (30) | 0 | (30) | 0
Net realized investment gains on disposals | 2,883 | 54 | 6,327 | 4,785
Proceeds from sale of fixed income securities, AFS | 153,700 | 262,900 | 372,159 | 938,276
Proceeds from sale of equity securities | 26,400 | 2,900 | 30,094 | 43,590
Fixed Maturities [Member] |  |  |  |
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
AFS securities Gains | 2,643 | 1,971 | 4,487 | 4,594
AFS securities Losses | $ (568) | $ (3,145) | $ (1,269) | $ (9,105)

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