Consolidated Statements Of Financial Condition (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Consolidated Statements Of Financial Condition [Abstract]
Trading securities pledged	$ 352,283	$ 393,888
Investments at fair value	$ 214,761	$ 211,208
Preferred stock, par value	$ 1	$ 1
Exchangeable common stock, par value	$ 0.15	$ 0.15
Exchangeable common stock, shares issued	0	172,242
Common stock, par value	$ 0.15	$ 0.15
Common stock, shares authorized	97,000,000	97,000,000
Common stock, shares issued	53,720,013	53,547,774
Treasury stock, shares	65,275	1,769,096
Unearned employee stock ownership plan, shares	36,608	73,215