Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Contingency [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%	21.00%	21.00%
Affiliated Funds
Income Tax Contingency [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 2.9	$ 2.4	$ 6.1	$ 4.8
U.S. Federal, State, Local and Foreign Taxes
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, percent	28.00%	24.20%	19.00%	24.20%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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