Increase (Decrease) of Long-term Debt

No definition available.

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Namespace Prefix:	jef_
Data Type:	xbrli:monetaryItemType
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

Long-Term Debt - Summary of Long-Term Debt Carrying Values Including Unamortized Discounts and Premiums (Detail) - USD ($) $ in Thousands	3 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Nov. 30, 2017
Debt Instrument [Line Items]
Long-term debt	$ 7,175,550		$ 6,416,844
3.875% Convertible Senior Debentures
Debt Instrument [Line Items]
Debt instrument interest rate	3.875%
Structured notes
Debt Instrument [Line Items]
Long-term debt	$ 742,777		614,091
Unsecured Debt \| 5.125% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 669,586		682,338
Debt instrument interest rate	5.125%
Effective Interest Rate	2.93%
Unsecured Debt \| 8.500% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 721,677		728,872
Debt instrument interest rate	8.50%
Effective Interest Rate	4.00%
Unsecured Debt \| 2.375% Euro Medium Term Notes
Debt Instrument [Line Items]
Long-term debt	$ 608,789		593,334
Debt instrument interest rate	2.375%
Effective Interest Rate	2.42%
Unsecured Debt \| 6.875% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 804,138		808,157
Debt instrument interest rate	6.875%
Effective Interest Rate	4.40%
Unsecured Debt \| 2.250% Euro Medium Term Notes
Debt Instrument [Line Items]
Long-term debt	$ 4,521		4,389
Debt instrument interest rate	2.25%
Effective Interest Rate	4.08%
Unsecured Debt \| 5.125% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 615,021		615,703
Debt instrument interest rate	5.125%
Effective Interest Rate	4.55%
Unsecured Debt \| 4.850% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 713,762		736,357
Debt instrument interest rate	4.85%
Effective Interest Rate	4.93%
Unsecured Debt \| 6.450% Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 375,274		375,794
Debt instrument interest rate	6.45%
Effective Interest Rate	5.46%
Unsecured Debt \| 3.875% Convertible Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 0		324,779
Debt instrument interest rate	3.875%
Effective Interest Rate	0.00%
Unsecured Debt \| 4.150% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 987,157		0
Debt instrument interest rate	4.15%
Effective Interest Rate	4.26%
Unsecured Debt \| 6.250% Senior Debentures
Debt Instrument [Line Items]
Long-term debt	$ 511,947		512,040
Debt instrument interest rate	6.25%
Effective Interest Rate	6.03%
Unsecured Debt \| 6.500% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 420,901		$ 420,990
Debt instrument interest rate	6.50%
Effective Interest Rate	6.09%
Interest Rate Swap [Member] \| Unsecured Debt \| 4.850% Senior Notes
Debt Instrument [Line Items]
Increase (Decrease) of Long-term Debt	$ (22,700)	$ (5,400)