Consolidated Statement of Financial Condition (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Nov. 30, 2011	Nov. 30, 2010
Consolidated Statement of Financial Condition [Abstract]
Securities pledged to creditors	$ 12,452,970	$ 12,338,728
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	197,197,848	200,301,656
Treasury stock, at cost	37,842	28,607,510