Consolidated Statements of Financial Condition (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Condensed Consolidated Statements of Financial Condition
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	52,456,165	52,300,885
Common stock held in treasury, at cost; shares	19,830,032	19,207,419