Investments - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investment Securities - fair value
Cost	$ 37,097	$ 55,882
Fair Value	35,460	60,990
Sponsored funds
Investment Securities - fair value
Cost	26,188	44,588
Fair Value	24,825	47,654
Equity securities
Investment Securities - fair value
Cost	10,902	11,250
Fair Value	10,629	13,320
Debt securities
Investment Securities - fair value
Cost	7	44
Fair Value	$ 6	$ 16