Investments in Securities and Fair Value Investments in Securities (Schedule of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Due in one year or less	$ 38,775
Due after one year through five years	56,388
Due five years through ten years	16,058
Due after ten years	816
Total	112,037	$ 100,667
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Due in one year or less	38,861
Due after one year through five years	59,930
Due five years through ten years	17,521
Due after ten years	1,401
Total	$ 117,713