Investments in Securities and Fair Value Investments in Securities (Schedule of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Due in one year or less	$ 12,920
Due after one year through five years	37,041
Due after five years through ten years	1,370
Due after ten years	2,444
Total, amortized cost	53,775	$ 75,511
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Due in one year or less	12,936
Due after one year through five years	37,079
Due after five years through ten years	1,396
Due after ten years	2,578
Total	$ 53,989

Available-For-Sale Debt Securities Estimated Fair Value

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