Consolidated Statements of Financial Condition (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Cash and cash equivalents, restricted from use	$ 7,055	$ 7,300
Advisory fees receivable, allowance for doubtful accounts	0	100
Property and equipment, accumulated depreciation	$ 54,760	$ 50,193
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	36,513,507	35,775,557
Common stock, shares outstanding	28,148,754	28,647,312
Contingent convertible preferred stock, par value	$ 0.01	$ 0.01
Contingent convertible preferred stock, shares authorized	10,000,000	10,000,000
Contingent convertible preferred stock, shares issued	1,099,877	1,099,877
Contingent convertible preferred stock, shares outstanding	1,099,877	1,099,877
Exchangeable shares of subsidiary, shares issued	257,156	257,156
Exchangeable shares of subsidiary, shares outstanding	32,804	110,191
Treasury stock, par value	$ 0.01	$ 0.01
Treasury stock, shares	9,024,679	7,128,245