Investments in Securities and Fair Value Investments in Securities (Schedule of Equity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, cost	$ 29,478	$ 32,478
Common stocks	76,853	64,919
Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, cost	29,478	32,478
Common stocks	$ 76,853	$ 64,919