Goodwill and Intangible Assets (Schedule of Components of Intangible Assets) (Details) - Advisory Contracts [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 20,803	$ 20,803
Accumulated amortization	13,585	12,641
Net amount	$ 7,218	$ 8,162