Consolidated Statements of Condition (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Consolidated Statements of Condition
Held-to-Maturity Investment Securities, Fair Value (in dollars)	$ 2,566,621	$ 134,028
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, authorized shares	500,000,000	500,000,000
Common Stock, issued shares	57,132,830	57,115,287
Common Stock, outstanding shares	47,225,303	48,097,672
Treasury Stock, Shares	9,907,527	9,017,615