Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Cash and securities segregated, at cost	$ 542,166	$ 859,448
Limited partners, units issued (in units)	285,586,728	286,609,212
Limited partners, units outstanding (in shares)	285,586,728	286,609,212

The number of limited partner units outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-5

Name:	us-gaap_LimitedPartnersCapitalAccountUnitsOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant