Collateralized Transactions - Summary of Repurchase Agreements and Securities Borrowing and Lending Arrangements (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015	Nov. 30, 2014
Banking and Thrift [Abstract]
Securities borrowing arrangements, Gross amounts	$ 6,566,376us-gaap_SecuritiesBorrowedGross	$ 6,853,103us-gaap_SecuritiesBorrowedGross
Securities borrowing arrangements, Netting in consolidated statement of financial condition	0	0
Securities borrowing arrangements, Net amounts in consolidated statement of financial condition	6,566,376us-gaap_SecuritiesBorrowed	6,853,103us-gaap_SecuritiesBorrowed
Securities borrowing arrangements, Additional amounts available for setoff	(526,142)	(680,222)
Securities borrowing arrangements, Available collateral	(766,832)	(1,274,196)
Securities borrowing arrangements, Net amount	5,273,402jef_SecuritiesBorrowedNetExposure	4,898,685jef_SecuritiesBorrowedNetExposure
Reverse repurchase agreements, Gross amounts	11,109,009	14,059,133
Reverse repurchase agreements, Netting in consolidated statement of financial condition	(7,363,321)	(10,132,275)
Reverse repurchase agreements, Net amounts in consolidated statement of financial condition	3,745,688	3,926,858
Reverse repurchase agreements, Additional amounts available for setoff	(236,325)	(634,568)
Reverse repurchase agreements, Available collateral	(3,450,577)	(3,248,817)
Reverse repurchase agreements, Net amount	58,786	43,473
Securities lending arrangements, Gross amounts	3,173,512us-gaap_SecuritiesLoanedGross	2,598,487us-gaap_SecuritiesLoanedGross
Securities lending arrangements, Netting in consolidated statement of financial condition	0	0
Securities loaned	3,173,512us-gaap_SecuritiesLoaned	2,598,487us-gaap_SecuritiesLoaned
Securities lending arrangements, Additional amounts available for setoff	(526,142)	(680,222)
Securities lending arrangements, Available collateral	(2,616,154)	(1,883,140)
Securities lending arrangements, Net amount	31,216jef_SecuritiesLoanedNetExposure	35,125jef_SecuritiesLoanedNetExposure
Repurchase agreements, Gross amounts	18,686,688	20,804,432
Repurchase agreements, Netting in consolidated statement of financial condition	(7,363,321)	(10,132,275)
Securities sold under agreements to repurchase	11,323,367	10,672,157
Repurchase agreements, Additional amounts available for setoff	(236,325)	(634,568)
Repurchase agreements, Available collateral	(10,039,131)	(8,810,770)
Repurchase agreements, Net amount	$ 1,047,911jef_RepurchaseAgreementsNetExposure	$ 1,226,819jef_RepurchaseAgreementsNetExposure

Repurchase Agreements Net Exposure

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Securities Borrowed Net Exposure

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- Definition

Securities Loaned Net Exposure

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No definition available.

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- Definition

Securities Purchased Under Agreements To Resell Net Exposure

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No definition available.

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Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount, after effects of master netting arrangements, of securities borrowed from entities in exchange for collateral offset against an obligation to return collateral under a master netting arrangement. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of the securities received as collateral against securities borrowed.

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Amount, before effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of securities borrowed from entities in exchange for collateral, not subject to a master netting arrangement.

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Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Amount, after effects of master netting arrangements, of securities loaned to entities in exchange for collateral offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of the securities pledged as collateral against securities loaned.

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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of securities loaned to entities in exchange for collateral, not subject to a master netting arrangement.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

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Amount, after effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of securities received as collateral against securities purchased under agreement to resell.

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Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price, not subject to a master netting arrangement.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount, after effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

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Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price, not subject to a master netting arrangement.

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