Condensed Consolidated Statements of Financial Condition (Parenthetical) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Class A units
Common stock, par value
Common stock, shares authorized	Unlimited	Unlimited
Common stock, shares issued	30,180,933	22,664,100
Common stock, shares outstanding	30,180,933	22,664,100
Class B units
Common stock, par value
Common stock, shares authorized	Unlimited	Unlimited
Common stock, shares issued	120,250,753	125,847,115
Common stock, shares outstanding	120,250,753	125,847,115
Class C units
Common stock, par value
Common stock, shares authorized	Unlimited	Unlimited
Common stock, shares issued	0	13,000
Common stock, shares outstanding	0	13,000