Consolidated Balance Sheets (Parenthetical) (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Investment securities
Investment securities, fair value	$ 528,458	$ 462,657
Real Estate Owned, Valuation Allowance	$ 36,873	$ 32,911
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 0.00006	$ 0.00006
Common stock, authorized (in shares)	2,500,000,000	2,500,000,000
Common stock, shares issued (in shares)	72,415,346	71,533,354
Common stock, shares outstanding (in shares)	72,415,346	71,533,354
Treasury stock, shares at cost (in shares)	4,087,995	3,380,310