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, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt and equity securities, realized gains	$ 11,020	$ 1,952
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Recognized in Earnings	(172)	0
Debt and equity securities, realized losses	(919)	(1,041)
Debt and equity securities, net realized gain (loss)	10,101	911
Gains (losses) on other assets and investments	(366)	958
Gain (Loss) on Disposition of Other Assets	(366)	958
Net realized investment gains (losses)	9,735	1,869
General obligations of U.S. states, territories and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt securities, realized losses	(353)	0
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, realized gains	0	52
Debt securities, realized losses	(104)	(33)
Common stocks and nonredeemable preferred stocks
Debt Securities, Available-for-sale [Line Items]
Equity securities, realized gains	11,020	1,900
Equity Securities, FV-NI, Realized Loss	(290)	(1,008)
Other than temporary impairment of securities
Debt Securities, Available-for-sale [Line Items]
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Recognized in Earnings	$ (172)	$ 0

Amount of realized gain on investments 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).

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings.

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Amount of realized gain (loss) on investment.

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