Fair Value Measurements for Operating Entities and Consolidated Funds - Assets and Liabilities at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands		Sep. 30, 2021		Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		$ 212,421		$ 51,482
Other investments		262,431		255,027
Other Investments, Consolidated Funds		100,252		192,670
Investments		4,532,969		2,511,403
Securities sold, not yet purchased, at fair value		1,361,723		728,115
Securities sold, not yet purchased, at fair value		1,361,723		728,115
Payable for derivative contracts, at fair value		46,872		76,160
Quarton
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low		10,100		10,100
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		25,000		35,100
Equity Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		320,825		64,634
Payable for derivative contracts, at fair value		146,837		43,560
Options (held long)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value	[1]	44,370		49,102
Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		518		0
Futures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		261		0
Portfolio Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	[2]	138,023		133,454
Other Investments, Consolidated Funds	[2]	100,252		192,670
Carried interest
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	[2]	84,312		82,892
Equity Method Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	[2]	40,096		38,681
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Recurring		4,170,286		2,063,706
Investment Sold, Not yet Purchased and Derivative Liability, at Fair Value		1,437,648		840,993
Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Recurring		3,694,891		1,847,389
Investment Sold, Not yet Purchased and Derivative Liability, at Fair Value		1,399,124		777,908
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Recurring		442,452		151,125
Investment Sold, Not yet Purchased and Derivative Liability, at Fair Value		147,417		57,281
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Recurring		186,958		127,461
Investment Sold, Not yet Purchased and Derivative Liability, at Fair Value		32,387		42,837
Fair Value, Measurements, Recurring | Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value				1,500
Fair Value, Measurements, Recurring | Government Securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value				0
Fair Value, Measurements, Recurring | Government Securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value				0
Fair Value, Measurements, Recurring | Government Securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value				1,500
Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		1,352,771		699,894
Fair Value, Measurements, Recurring | Common Stock | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		1,352,771		699,894
Fair Value, Measurements, Recurring | Common Stock | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Common Stock | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Corporate Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		40		11,358
Fair Value, Measurements, Recurring | Corporate Bonds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Corporate Bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		40		10,654
Fair Value, Measurements, Recurring | Corporate Bonds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		704
Fair Value, Measurements, Recurring | Preferred Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		6,624		6,589
Fair Value, Measurements, Recurring | Preferred Stock | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		6,624		6,589
Fair Value, Measurements, Recurring | Preferred Stock | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Preferred Stock | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Warrants and Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		2,288		8,774
Fair Value, Measurements, Recurring | Warrants and Rights | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		2,288		8,774
Fair Value, Measurements, Recurring | Warrants and Rights | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Warrants and Rights | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities sold, not yet purchased, at fair value		0		0
Fair Value, Measurements, Recurring | Contingent liability payable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration Payable		29,053	[3]	36,718	[4]
Fair Value, Measurements, Recurring | Contingent liability payable | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration Payable		0	[3]	0	[4]
Fair Value, Measurements, Recurring | Contingent liability payable | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration Payable		0	[3]	0	[4]
Fair Value, Measurements, Recurring | Contingent liability payable | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration Payable		29,053	[3]	36,718	[4]
Fair Value, Measurements, Recurring | Currency forward | Derivative Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		22		3,067
Fair Value, Measurements, Recurring | Currency forward | Derivative Liabilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Currency forward | Derivative Liabilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		22		3,067
Fair Value, Measurements, Recurring | Currency forward | Derivative Liabilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Equity Swaps | Derivative Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		5,557		6,527
Fair Value, Measurements, Recurring | Equity Swaps | Derivative Liabilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Equity Swaps | Derivative Liabilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		146,837		43,560
Fair Value, Measurements, Recurring | Equity Swaps | Derivative Liabilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	[5]	(141,280)		(37,033)
Fair Value, Measurements, Recurring | Options (held long) | Derivative Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		40,514		66,566
Fair Value, Measurements, Recurring | Options (held long) | Derivative Liabilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		37,180		62,651
Fair Value, Measurements, Recurring | Options (held long) | Derivative Liabilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Options (held long) | Derivative Liabilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		3,334		3,915
Fair Value, Measurements, Recurring | Interest rate swap | Derivative Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		518
Fair Value, Measurements, Recurring | Interest rate swap | Derivative Liabilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0
Fair Value, Measurements, Recurring | Interest rate swap | Derivative Liabilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		518
Fair Value, Measurements, Recurring | Interest rate swap | Derivative Liabilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0
Fair Value, Measurements, Recurring | Futures | Derivative Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		261
Fair Value, Measurements, Recurring | Futures | Derivative Liabilities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		261
Fair Value, Measurements, Recurring | Futures | Derivative Liabilities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0
Fair Value, Measurements, Recurring | Futures | Derivative Liabilities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable for derivative contracts, at fair value		0
Fair Value, Measurements, Recurring | Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		21,936		19,721
Fair Value, Measurements, Recurring | Government Securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		21,936		19,721
Fair Value, Measurements, Recurring | Government Securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Government Securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Preferred Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		117,922		69,358
Fair Value, Measurements, Recurring | Preferred Stock | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		11,674		9,391
Fair Value, Measurements, Recurring | Preferred Stock | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		0		0
Fair Value, Measurements, Recurring | Preferred Stock | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		106,248		59,967
Fair Value, Measurements, Recurring | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		3,634,290		1,770,301
Fair Value, Measurements, Recurring | Common Stock | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		3,592,861		1,746,407
Fair Value, Measurements, Recurring | Common Stock | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		79		108
Fair Value, Measurements, Recurring | Common Stock | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		41,350		23,786
Fair Value, Measurements, Recurring | Convertible Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		7,363		6,040
Fair Value, Measurements, Recurring | Convertible Bonds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Convertible Bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Convertible Bonds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		7,363		6,040
Fair Value, Measurements, Recurring | Corporate Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		120,390		86,503
Fair Value, Measurements, Recurring | Corporate Bonds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Corporate Bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		120,307		86,368
Fair Value, Measurements, Recurring | Corporate Bonds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		83		135
Fair Value, Measurements, Recurring | Trade Claims
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		5,681		8,713
Fair Value, Measurements, Recurring | Trade Claims | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Trade Claims | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Trade Claims | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		5,681		8,713
Fair Value, Measurements, Recurring | Term Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		12,578		12,623
Fair Value, Measurements, Recurring | Term Loans | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Term Loans | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		0		0
Fair Value, Measurements, Recurring | Term Loans | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading		12,578		12,623
Fair Value, Measurements, Recurring | Private Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		361		642
Fair Value, Measurements, Recurring | Private Investments | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		0		0
Fair Value, Measurements, Recurring | Private Investments | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		0		0
Fair Value, Measurements, Recurring | Private Investments | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		361		642
Fair Value, Measurements, Recurring | Warrants and Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		34,393		27,701
Fair Value, Measurements, Recurring | Warrants and Rights | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		21,337		21,154
Fair Value, Measurements, Recurring | Warrants and Rights | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		0		0
Fair Value, Measurements, Recurring | Warrants and Rights | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		13,056		6,547
Fair Value, Measurements, Recurring | Derivative Assets | Currency forward
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		1,241		15
Fair Value, Measurements, Recurring | Derivative Assets | Currency forward | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Derivative Assets | Currency forward | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		1,241		15
Fair Value, Measurements, Recurring | Derivative Assets | Currency forward | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Derivative Assets | Equity Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		166,810		2,365
Fair Value, Measurements, Recurring | Derivative Assets | Equity Swaps | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Derivative Assets | Equity Swaps | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		320,825		64,634
Fair Value, Measurements, Recurring | Derivative Assets | Equity Swaps | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		0		0
Derivative Asset, Fair Value, Amount Offset Against Collateral	[5]	(154,015)		(62,269)
Fair Value, Measurements, Recurring | Derivative Assets | Options (held long)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		44,370		49,102
Fair Value, Measurements, Recurring | Derivative Assets | Options (held long) | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		44,132		48,851
Fair Value, Measurements, Recurring | Derivative Assets | Options (held long) | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		0		0
Fair Value, Measurements, Recurring | Derivative Assets | Options (held long) | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable on derivative contracts, at fair value		238		251
Fair Value, Measurements, Recurring | Consolidated Funds | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		2,951		4,816
Fair Value, Measurements, Recurring | Consolidated Funds | Common Stock | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		2,951		1,865
Fair Value, Measurements, Recurring | Consolidated Funds | Common Stock | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		0		0
Fair Value, Measurements, Recurring | Consolidated Funds | Common Stock | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity		$ 0		2,951
Fair Value, Measurements, Recurring | Consolidated Funds | Warrants and Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity				5,806
Fair Value, Measurements, Recurring | Consolidated Funds | Warrants and Rights | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity				0
Fair Value, Measurements, Recurring | Consolidated Funds | Warrants and Rights | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity				0
Fair Value, Measurements, Recurring | Consolidated Funds | Warrants and Rights | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading Securities, Equity				$ 5,806

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

[2] In accordance with US GAAP, portfolio funds are measured at fair value using the net asset value per share (or its equivalent) as a practical expedient are not classified in the fair value hierarchy. Carried interest and equity method investments presented in the table above are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the condensed consolidated statement of financial condition.

[3] In accordance with the terms of the purchase agreements for acquisitions that closed during the first quarter of 2019 and the fourth quarter of 2020, the Company is required to pay to the sellers a portion of future net income and/or revenues of the acquired businesses, if certain targets are achieved through the periods ended December 31, 2020 and December 31, 2023. For both the Quarton acquisition, completed during the first quarter of 2019, and the MHT acquisition, completed during the fourth quarter of 2020, the Company estimated the contingent consideration liabilities using a combination of Monte Carlo and Discounted Cash Flow methods which require the Company to make estimates and assumptions regarding the future cash flows and profits. Changes in these estimates and assumptions could have a significant impact on the amounts recognized. The undiscounted amounts for the Quarton acquisition can range from $10.1 million to $25.0 million. The undiscounted amounts for the MHT acquisition have no minimum or maximum as it is calculated based on revenue.

[4] In accordance with the terms of the purchase agreements for acquisitions that closed during the first quarter of 2019 and the fourth quarter of 2020, the Company is required to pay to the sellers a portion of future net income and/or revenues of the acquired businesses, if certain targets are achieved through the periods ended December 31, 2020 and December 31, 2023. For both the Quarton acquisition, completed during the first quarter of 2019, and the MHT acquisition, completed during the fourth quarter of 2020, the Company estimated the contingent consideration liabilities using a combination of Monte Carlo and Discounted Cash Flow methods which require the Company to make estimates and assumptions regarding the future cash flows and profits. Changes in these estimates and assumptions could have a significant impact on the amounts recognized. The undiscounted amounts for the Quarton acquisition can range from $10.1 million to $35.1 million. The undiscounted amounts for the MHT acquisition have no minimum or maximum as it is calculated based on revenue.

[5] 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.