Document and Entity Information	9 Months Ended
	Aug. 31, 2017 shares
Document And Entity Information [Abstract]
Entity Registrant Name	JEFFERIES GROUP LLC
Entity Central Index Key	0001084580
Current Fiscal Year End Date	--11-30
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Aug. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding	0