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Investments - Schedule of Net Realized and Unrealized Investment Gains and (Losses) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Gain (Loss) on Securities [Line Items] |  |
Gross gains on sales | $ 1,727 | $ 2,135
Gross losses on sales | (2,383) | (1,965)
Net realized gains (losses) on disposals | (656) | 170
Net unrealized gains (losses) on equity securities | 1,050 | 692
Losses on securities for which we have the intent to sell | (759) | (15)
Net realized and unrealized investment gains (losses) | 229 | (1,635)
Debt Securities, Available-For-Sale |  |
Gain (Loss) on Securities [Line Items] |  |
Net credit loss benefit (expense) | 629 | (2,650)
Commercial mortgage loans ("CMLs") |  |
Gain (Loss) on Securities [Line Items] |  |
Net credit loss benefit (expense) | $ (35) | $ 168

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