Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net investment gains (losses)
Available-for-sale	$ (442)	$ (1,397)	$ (277)
Allowance for Credit Losses	(1)	(3)	5
Net gains (losses) recognized on equity securities sold during the period	150	(1,767)	14,444
Unrealized gains (losses) recognized during the period on equity securities still held at reporting date	1,842	(12,802)	30,682
Net gains (losses) recognized during the reporting period on equity securities	1,992	(14,569)	45,126
Mortgage loans	(5)	109	5
Other long-term assets	(319)	(267)	2,780
Real Estate	47	235	(256)
Net Realized Investment Gains (Losses)	1,274	(15,892)	47,383
Proceeds from sales	77,388	83,559	180,514
Gross realized gains	265	459	843
Gross realized losses	$ 707	$ 1,857	$ 1,120

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with previously recorded allowance and not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis.

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