Investments in Securities and Fair Value Investments in Securities (Schedule of Gross Realized Gains and Losses on Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Gross realized gains from securities	$ 5,525	$ 16,350
Impairment of securities	(74)	(201)
Gross realized losses from securities	(437)	(601)
Debt and equity securities, net realized gain (loss)	5,088	15,749
Impairment of other assets and investments	(309)	0
Gains on other investments	242	5
Losses on other investments	(20)	(123)
Net gains (losses) on other investments	(87)	(118)
Net realized investment gains (losses)	5,001	15,631
Unrealized gain (loss) on investments	(318)	(12,183)
Net investment gains	4,683	3,448
Common stocks and nonredeemable preferred stocks
Debt Securities, Available-for-sale [Line Items]
Equity securities, realized gains	5,525	16,350
Equity securities, realized loss	$ (363)	$ (400)

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