Investments Of Operating Entities And Consolidated Funds - Operating Entities - Receivable On And Payable For Derivative Contracts, At Fair Value (Details)		Mar. 31, 2021 USD ($) contract	Dec. 31, 2020 USD ($) contract
Derivative [Line Items]
Receivable on derivative contracts, at fair value		$ 95,536,000	$ 51,482,000
Payable for derivative contracts, at fair value		52,125,000	76,160,000
Receivable on derivatives contracts, at fair value [Member]
Derivative [Line Items]
Receivable on derivative contracts, at fair value		95,536,000	51,482,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	[1],[2]	(89,238,000)	(62,269,000)
Payable for derivatives contracts, at fair value [Member]
Derivative [Line Items]
Payable for derivative contracts, at fair value		52,125,000	76,160,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	[2]	(61,806,000)	(37,033,000)
Currency Forwards
Derivative [Line Items]
Derivative Asset, Notional Amount		132,960,000	4,902,000
Receivable on derivative contracts, at fair value		384,000	15,000
Derivative Liability, Notional Amount		1,990,000	123,346,000
Payable for derivative contracts, at fair value		16,000	3,067,000
Swaps
Derivative [Line Items]
Derivative Asset, Notional Amount		1,746,919,000	944,544,000
Receivable on derivative contracts, at fair value		142,266,000	64,634,000
Derivative Liability, Notional Amount		1,603,710,000	896,863,000
Payable for derivative contracts, at fair value		$ 82,391,000	$ 43,560,000
Options
Derivative [Line Items]
Derivative Asset, Number of Instruments Held | contract	[3]	163,622	371,188
Receivable on derivative contracts, at fair value	[3]	$ 42,124,000	$ 49,102,000
Option
Derivative [Line Items]
Derivative Liability, Number of Instruments Held | contract	[3]	130,627	198,320
Payable for derivative contracts, at fair value	[3]	$ 31,524,000	$ 66,566,000

[1] Derivatives are reported on a net basis, by counterparty, when a legal right of offset exists under an enforceable netting agreement as well as net of cash collateral received or posted under enforceable credit support agreements. See Note 2f for further information on offsetting of derivative financial instruments.

[2] Includes financial instruments subject to enforceable master netting provisions that are permitted to be offset to the extent an event of default has occurred

[3] Includes the volume of contracts for index, equity, commodity future and cash conversion options.