Consolidated Company-Sponsored Investment Funds (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Derivative [Line Items]
Gains (losses) on derivative instruments	$ (9,117)	$ (419)	$ (28,882)	$ 1,948
Cash collateral payable to trade counterparties	300		300		$ 4,800
Cash collateral received	6,900		6,900		4,500
Net assets of investment products that are non-consolidated VIEs	100,900,000		100,900,000
Maximum risk of loss in investment in VIEs	13,100		13,100
VIEs
Derivative [Line Items]
Futures, forwards and swaps held	100		100		500
Gains (losses) on derivative instruments	1,600	15,800	2,700	900
Cash collateral payable to trade counterparties	1,351		1,351		856
Cash collateral received	2,700		2,700		800
VOEs
Derivative [Line Items]
Futures, forwards and swaps held	100		100		100
Gains (losses) on derivative instruments	(600)	$ 1,800	(500)	$ 1,300
Cash collateral payable to trade counterparties	422		422		225
Cash collateral received	$ 800		$ 800		$ 500

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

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