Consolidated Company-Sponsored Investment Funds (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Derivative [Line Items]
Gains (losses) on derivative instruments	$ (115)	$ (5,755)	$ (28,997)	$ (3,807)
Cash collateral payable to trade counterparties	300		300		$ 4,800
Cash collateral received	1,900		1,900		4,500
Net assets of investment products that are non-consolidated VIEs	72,000,000		72,000,000
Maximum risk of loss in investment in VIEs	11,000		11,000
VIEs
Derivative [Line Items]
Futures, forwards and swaps held	100		100		500
Gains (losses) on derivative instruments	600	(500)	3,300	400
Cash collateral payable to trade counterparties	1,351		1,351		856
Cash collateral received	3,400		3,400		800
VOEs
Derivative [Line Items]
Futures, forwards and swaps held	2,600		2,600		100
Gains (losses) on derivative instruments	1,000	$ 200	500	$ 1,500
Cash collateral payable to trade counterparties	597		597		225
Cash collateral received	$ 1,300		$ 1,300		$ 500

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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