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Investments - Schedule of Net Realized and Unrealized Investment Gains and (Losses) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Gain (Loss) on Securities [Line Items] |  |  |  |
Gross gains on sales | $ 4,159 | $ 367 | $ 10,681 | $ 5,307
Gross losses on sales | (2,012) | (5,264) | (5,228) | (30,146)
Net realized gains (losses) on disposals | 2,147 | (4,897) | 5,453 | (24,839)
Net unrealized gains (losses) on equity securities | 2,407 | 489 | 3,006 | 8,662
Losses on securities for which we have the intent to sell | (752) | 0 | (1,248) | (645)
Other realized gains (losses) | (602) | 0 | (602) | 0
Net realized and unrealized investment gains (losses) | 5,389 | (6,880) | 5,051 | (8,962)
Available-for-Sale Securities |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net credit loss benefit (expense) | 2,191 | (2,468) | (1,692) | 7,925
Commercial mortgage loans ("CMLs") |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net credit loss benefit (expense) | $ (2) | $ (4) | $ 134 | $ (65)

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