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Investments (Net Realized Gains (Losses) on Disposals) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
HTM gains (losses) | $ 1 | $ 0 | $ 2 | $ 1
CMLs gains | 1 | 0 | 2 | 0
CMLs losses | 0 | 0 | 0 | 0
Equity securities Gains | 0 | 21,630 | 0 | 24,868
Equity securities Losses | 0 | (28) | (3) | (135)
Short-term investments Gains | 18 | 2 | 355 | 18
Short-term investments Losses | (7) | (38) | (198) | (39)
Other investments Gains | 0 | 0 | 0 | 7
Other investments Losses | 0 | 0 | (5) | (30)
Net realized investment gains on disposals | 573 | 20,425 | 7,288 | 26,752
Gain (Loss) on Investments [Member] |  |  |  |
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
HTM gains (losses) | 0 | 0 | 0 | (15)
Available-for-sale Securities |  |  |  |
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items] |  |  |  |
AFS fixed income securities Gains | 2,955 | 1,078 | 14,770 | 5,565
AFS fixed income securities Losses | $ (2,395) | $ (2,219) | $ (7,635) | $ (3,488)

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