Leucadia and Related Transactions - Assets Acquired and Liabilities Assumed by Major Class (Detail) (Leucadia [Member], USD $) In Thousands, unless otherwise specified	Feb. 28, 2013
Assets acquired:
Cash and cash equivalents	$ 3,017,958
Cash and securities segregated	3,728,742
Financial instruments owned, at fair value	16,413,535
Investments in managed funds	59,976
Loans to and investments in related parties	766,893
Securities borrowed	5,315,488
Securities purchased under agreements to resell	3,578,366
Securities received as collateral	25,338
Brokers, dealers and clearing organizations	2,444,085
Customers	1,045,251
Fees, interest and other	225,555
Premises and equipment	192,603
Indefinite-lived intangible exchange memberships and licenses	15,551
Other assets	939,600
Total assets	38,036,242
Liabilities assumed:
Short-term borrowings	100,000
Financial instruments sold, not yet purchased, at fair value	9,766,876
Securities loaned	1,902,687
Securities sold under agreements to repurchase	7,976,492
Other secured financings	122,294
Obligation to return securities received as collateral	25,338
Brokers, dealers and clearing organizations	1,787,055
Customers	5,450,781
Accrued expenses and other liabilities	793,843
Long-term debt	6,362,024
Mandatorily redeemable preferred interests	358,951
Total liabilities	34,646,341
Noncontrolling interests	356,180
Fair value of net assets acquired, excluding goodwill	3,033,721
Goodwill	1,720,380
Customer relationships [Member]
Assets acquired:
Finite-lived intangible assets	136,002
Trade name [Member]
Assets acquired:
Finite-lived intangible assets	$ 131,299