Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2013		Nov. 30, 2012
Financial instruments owned:
Corporate equity securities	$ 1,688,607		$ 1,762,775
Corporate debt securities	3,371,464		3,038,146
Collateralized debt obligations	144,921		118,494
U.S. government and federal agency securities	909,640		1,835,927
Municipal securities	603,957		619,969
Sovereign obligations	3,496,858		2,697,854
Mortgage- and asset-backed securities, assets	4,939,327		5,468,284
Loans and other receivables	968,360		678,311
Derivatives	206,920		298,086
Investments at fair value	71,103		127,023
Physical commodities	157,299		144,016
Total financial instruments owned	16,413,535		16,670,391
Cash and cash equivalents	3,017,958		2,692,595
Investments in managed funds	59,976		57,763
Cash and securities segregated and on deposit for regulatory purposes	3,728,742	[1],[2]	4,082,595	[1],[3]
Securities received as collateral	25,338		0
Financial instruments sold, not yet purchased:
Corporate equity securities	1,934,184		1,539,332
Corporate debt securities	1,845,617		1,389,312
U.S. government and federal agency securities	2,567,397		1,679,133
Sovereign obligations	2,477,844		1,986,979
Mortgage- and asset-backed securities, liabilities	101,580		241,211
Loans	452,007		207,227
Derivatives	220,697		229,127
Physical commodities	167,550		183,142
Total financial instruments sold, not yet purchased	9,766,876		7,455,463
Obligation to return securities received as collateral	25,338
Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	3,789,636		4,164,913
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	96,074		239,063
Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	933,614		1,090,535
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	1,811		2,148
Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	71,156		94,342
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	3,695
Level 1 [Member]
Financial instruments owned:
Corporate equity securities	1,443,328	[4]	1,608,715	[5]
U.S. government and federal agency securities	776,846	[4]	1,720,617	[5]
Sovereign obligations	2,041,200	[4]	1,722,044	[5]
Derivatives	445,895	[4]	615,024	[5]
Total financial instruments owned	4,707,269	[4]	5,666,400	[5]
Cash and cash equivalents	3,017,958	[4]	2,692,595	[5]
Cash and securities segregated and on deposit for regulatory purposes	3,728,742	[2],[4]	4,082,595	[3],[5]
Securities received as collateral	25,338	[4]
Financial instruments sold, not yet purchased:
Corporate equity securities	1,697,826	[4]	1,442,347	[5]
U.S. government and federal agency securities	2,567,397	[4]	1,428,746	[5]
Sovereign obligations	1,268,489	[4]	1,395,355	[5]
Derivatives	435,602	[4]	547,605	[5]
Total financial instruments sold, not yet purchased	5,969,314	[4]	4,814,053	[5]
Obligation to return securities received as collateral	25,338	[4]
Level 2 [Member]
Financial instruments owned:
Corporate equity securities	232,045	[4]	137,245	[5]
Corporate debt securities	3,339,644	[4]	3,034,515	[5]
Collateralized debt obligations	115,145	[4]	87,239	[5]
U.S. government and federal agency securities	132,794	[4]	115,310	[5]
Municipal securities	603,957	[4]	619,969	[5]
Sovereign obligations	1,455,658	[4]	975,810	[5]
Loans and other receivables	797,374	[4]	497,918	[5]
Derivatives	1,491,718	[4]	1,547,984	[5]
Investments at fair value	1,036	[4]	43,126	[5]
Physical commodities	157,299	[4]	144,016	[5]
Total financial instruments owned	12,932,604	[4]	12,365,537	[5]
Financial instruments sold, not yet purchased:
Corporate equity securities	236,320	[4]	96,947	[5]
Corporate debt securities	1,845,617	[4]	1,389,312	[5]
U.S. government and federal agency securities			250,387	[5]
Sovereign obligations	1,209,355	[4]	591,624	[5]
Loans	444,609	[4]	205,516	[5]
Derivatives	1,640,905	[4]	1,684,884	[5]
Physical commodities	167,550	[4]	183,142	[5]
Total financial instruments sold, not yet purchased	5,644,394	[4]	4,643,023	[5]
Level 2 [Member] | Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	3,620,210	[4]	4,008,844	[5]
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	94,532	[4]	239,063	[5]
Level 2 [Member] | Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	915,820	[4]	1,060,333	[5]
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	1,811	[4]	2,148	[5]
Level 2 [Member] | Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	69,904	[4]	93,228	[5]
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	3,695	[4]
Level 3 [Member]
Financial instruments owned:
Corporate equity securities	13,234		16,815
Corporate debt securities	31,820		3,631
Collateralized debt obligations	29,776		31,255
Loans and other receivables	170,986		180,393
Derivatives	220		328
Investments at fair value	70,067		83,897
Total financial instruments owned	504,575		503,704
Level 3 financial instruments for which the firm does not bear economic exposure	(38,771)	[6]	(53,289)	[6]
Level 3 financial instruments for which the firm bears economic exposure	465,804		450,415
Investments in managed funds	59,976		57,763
Total Level 3 assets for which the firm bears economic exposure	525,780		508,178
Financial instruments sold, not yet purchased:
Corporate equity securities	38		38
Loans	7,398		1,711
Derivatives	11,405		9,516
Total financial instruments sold, not yet purchased	20,383		11,265
Level 3 [Member] | Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	169,426		156,069
Financial instruments sold, not yet purchased:
Mortgage- and asset-backed securities, liabilities	1,542
Level 3 [Member] | Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	17,794		30,202
Level 3 [Member] | Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,252		1,114
Counterparty and Cash Collateral Netting [Member]
Financial instruments owned:
Derivatives	(1,730,913)	[7]	(1,865,250)	[7]
Total financial instruments owned	(1,730,913)	[7]	(1,865,250)	[7]
Financial instruments sold, not yet purchased:
Derivatives	(1,867,215)	[7]	(2,012,878)	[7]
Total financial instruments sold, not yet purchased	$ (1,867,215)	[7]	$ (2,012,878)	[7]

[1] Consists of deposits at exchanges and clearing organizations, as well as deposits in accordance with Rule 15c3-3 of the Securities Exchange Act of 1934, which subjects Jefferies as a broker-dealer carrying client accounts to requirements related to maintaining cash or qualified securities in a segregated reserve account for the exclusive benefit of its clients, and Jefferies Bache, LLC which, as a futures commission merchant, is subject to the segregation requirements pursuant to the Commodity Exchange Act.

[2] Includes U.S. government securities segregated for regulatory purposes with a fair value of $357.2 million.

[3] Includes U.S. government securities segregated for regulatory purposes with a fair value of $404.3 million.

[4] There were no transfers between Level 1 and Level 2 for the three months ended February 28, 2013.

[5] There were no transfers between Level 1 and Level 2 for the year ended November 30, 2012.

[6] Consists of Level 3 assets attributable to third party or employee noncontrolling interests in certain consolidated entities.

[7] Represents counterparty and cash collateral netting across the levels of the fair value hierarchy for positions with the same counterparty.