BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Investment securities, held-to-maturity fair value	$ 330,809	$ 0
Other real estate owned, covered under loss sharing agreements with the FDIC	$ 6,166	$ 5,342
Shareholders' equity
Preferred stock, par value (in dollars per share)	$ 1,000	$ 1,000
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	11,395,302	8,398,015
Common stock, shares outstanding (in shares)	11,347,683	8,398,015
Treasury stock (in shares)	47,619	0
Common Class A [Member]
Shareholders' equity
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common Class B [Member]
Shareholders' equity
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0