Investments in Securities and Fair Value Investments in Securities (Schedule of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Due in one year or less	$ 9,695
Due after one year through five years	62,699
Due five years through ten years	27,461
Due after ten years	812
Total	100,667	$ 87,714
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Due in one year or less	9,740
Due after one year through five years	64,756
Due five years through ten years	28,847
Due after ten years	1,295
Total	$ 104,638