Related Party Transactions (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Sublease Income	$ 144,000	$ 0	$ 0
Sublease Income	144,000	0	0
UCITS Fund
Related Party Transaction [Line Items]
Fees earned from related party	2,800,000	4,200,000	$ 4,000,000.0
Fees unpaid from related party	200,000	$ 300,000
Trust
Related Party Transaction [Line Items]
Due from related party	100,000
Fees earned from related party	$ 400,000

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Amount of sublease income excluding finance and operating lease expense.

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