Other Real Estate (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Other Real Estate and Foreclosed Assets [Abstract]
Other real estate	$ 189,182,000		$ 189,182,000		$ 204,232,000
Loans foreclosed and transferred to other real estate			122,100,000	190,400,000
Foreclosed real estate expense, net	11,997,000	37,108,000	55,677,000	101,716,000
Write-downs to net realizable value and losses resulting from sales transactions	$ 8,800,000	$ 33,300,000	$ 42,695,000	$ 87,814,000