Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Nov. 30, 2021	Nov. 30, 2020
Leases [Abstract]
Year one	$ 68,315	$ 65,442
Year two	65,971	70,200
Year three	63,640	62,641
Year four	64,528	61,106
Year five	62,120	63,158
After year five	281,642
Year six		56,936
After year six		281,806
Total undiscounted cash flows	606,216	661,289
Less: Difference between undiscounted and discounted cash flows	(84,997)	(100,402)
Operating leases amount in our Consolidated Statement of Financial Condition	$ 521,219	$ 560,887
Operating lease, liability, statement of financial position [Extensible List]	JEF:OperatingLeaseAndFinanceLeaseLiability	JEF:OperatingLeaseAndFinanceLeaseLiability
Finance Lease, Liability, Statement of Financial Position [Extensible List]	JEF:OperatingLeaseAndFinanceLeaseLiability	JEF:OperatingLeaseAndFinanceLeaseLiability
Finance leases amount in our Consolidated Statement of Financial Condition	$ 229	$ 362
Total amount in our Consolidated Statement of Financial Condition	$ 521,448	$ 561,249

Lessee, Operating Lease, Liability, to be Paid, after Year Six

No definition available.

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- Definition

Lessee, Operating Lease, Liability, to be Paid, Year Six

+ References

No definition available.

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- Definition

Operating Lease And Finance Lease, Liability

+ References

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Indicates line item in statement of financial position that includes finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918631-209977

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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Indicates line item in statement of financial position that includes operating lease liability.

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