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Investments (Net Realized and Unrealized Investment Gains and (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Gain (Loss) on Securities [Line Items] |  |  |  |
Gross gains on sales | $ 14,552 | $ 2,079 | $ 16,749 | $ 5,755
Gross losses on sales | (19,345) | (1,811) | (32,905) | (6,282)
Net realized (losses) gains on disposals | (4,793) | 268 | (16,156) | (527)
Net unrealized (losses) gains on equity securities | (21,860) | 7,661 | (24,014) | 18,941
Losses on securities for which we have the intent to sell | (702) | (91) | (5,499) | (453)
Net realized and unrealized investment (losses) gains | (42,880) | 10,057 | (83,232) | 15,176
Change in net realized and unrealized investment gains | (52,900) |  | (98,400) |
Available-for-sale Securities [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net credit loss (expense) benefit on fixed income securities | (15,519) | 2,272 | (37,571) | (2,725)
Held-to-maturity Securities [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net credit loss (expense) benefit on fixed income securities | $ (6) | $ (53) | $ 8 | $ (60)

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