Consolidated Company-Sponsored Investment Funds - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Cash collateral payable to trade counterparties	$ 300	$ 4,800
Cash collateral received	4,300	4,500
Net assets of investment products that are non-consolidated VIEs	79,300,000
Maximum risk of loss in investment in VIEs	8,400
VIEs
Derivative [Line Items]
Futures, forwards and swaps held	300	500
Gains (losses) on derivatives	3,300	1,500
Cash collateral payable to trade counterparties	1,631	856
Cash collateral received	3,200	800
VOEs
Derivative [Line Items]
Futures, forwards and swaps held	(700)	100
Gains (losses) on derivatives	500	1,900
Cash collateral payable to trade counterparties	534	225
Cash collateral received	$ 1,200	$ 500

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