Collateralized Transactions - Additional Information (Details) - USD ($) $ in Thousands	Aug. 31, 2020	Nov. 30, 2019
Collateralized Transactions [Abstract]
Fair value of securities received as collateral	$ 29,900,000	$ 28,700,000
Cash and securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	$ 986,117	$ 796,797

Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

Name:	us-gaap_FairValueOfSecuritiesReceivedAsCollateralThatCanBeResoldOrRepledged
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant