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Investments (Net Realized and Unrealized Investment Gains and (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Gain (Loss) on Securities [Line Items] |  |
Gross gains on sales | $ 2,197 | $ 3,676
Gross losses on sales | (13,560) | (4,471)
Debt and Equity Securities, Realized Loss | (11,363) | (795)
Net unrealized (losses) gains on equity securities | (2,154) | 11,280
Losses on securities for which we have the intent to sell | (4,797) | (362)
Net realized and unrealized investment (losses) gains | (40,352) | 5,119
Available-for-sale Securities [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net credit loss benefit (expense) on fixed maturities | (22,052) | (4,997)
Held-to-maturity Securities [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net credit loss benefit (expense) on fixed maturities | $ 14 | $ (7)

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- Definition This item represents the gross gain realized on sales of debt and equity investments. + References No definition available. + Details
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