Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Held-to-maturity securities, fair value	$ 2,721,723	$ 2,690,546
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized	5,000,000	5,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	166,494,888	166,494,888
Common stock, shares outstanding	101,731,174	101,210,478
Treasury stock, shares	64,763,714	65,284,410
Series C Preferred Stock
Preferred stock, shares authorized	150,000	150,000
Preferred stock, shares issued	135,000	135,000
Preferred stock, shares outstanding	135,000	135,000