Consolidated Statements of Condition (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowance for loan losses	$ 37,746	$ 37,089
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	65,000,000	65,000,000
Common stock, issued	56,090,521	55,945,245
Treasury stock, shares	26,541,772	26,182,401