Investments - Net Realized and Unrealized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Equity securities:
Equity securities	$ 2,115	$ (3,663)
Net realized and unrealized investment gains (losses)	1,853	(5,282)
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	270	206
Gross realized losses	(532)	(1,825)
Net realized losses on available-for-sale securities	(262)	(1,619)
Equity securities
Equity securities:
Equity securities	$ 2,115	$ (3,663)

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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