Net Capital Requirements - Schedule of Net Capital and Excess Net Capital (Details) - Jefferies LLC $ in Thousands	Nov. 30, 2019 USD ($)
Net Capital Requirements [Line Items]
Net Capital	$ 1,644,980
Excess Net Capital	$ 1,527,951

Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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