Consolidated Company-Sponsored Investment Funds (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative [Line Items]
Gains (losses) on derivative instruments	$ 29,566	$ (19,765)
Cash collateral payable to trade counterparties	8,500		$ 300
Cash collateral received	9,600		4,300
Net assets of investment products that are non-consolidated VIEs	80,500,000
Maximum risk of loss in investment in VIEs	6,700
VIEs
Derivative [Line Items]
Futures, forwards and swaps held	1,300		300
Gains (losses) on derivative instruments	1,700	1,100
Cash collateral payable to trade counterparties including amounts that exceed fair value	33,100
Cash collateral payable to trade counterparties	7,892		1,631
Cash collateral received	59,000		3,200
VOEs
Derivative [Line Items]
Futures, forwards and swaps held	600		700
Gains (losses) on derivative instruments	(100)	$ 100
Cash collateral payable to trade counterparties	580		534
Cash collateral received	$ 2,800		$ 1,200

Derivative, Collateral, Obligation to Return Cash Including Amounts That Exceed Fair Value Of Assets

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

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

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