Loans (Nonperforming Assets) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Financing Receivable [Line Items]
Interest lost on nonaccrual loans	$ 1,500,000	$ 3,500,000	$ 2,900,000	$ 7,600,000
Loans on nonaccrual status	95,100,000		95,100,000		103,000,000
Loans held for sale on nonaccrual status	0		0		4,529,000
Loans more than 90 days delinquent, still on accrual	427,000		427,000		3,000,000
Real estate owned/repossessed assets	86,400,000		86,400,000		110,386,000
Total Assets	2,301,761,000		2,301,761,000		2,409,108,000
Nonperforming [Member]
Financing Receivable [Line Items]
Loans held for sale on nonaccrual status	0		0		4,529,000
Loans held for investment , nonaccrual status	95,110,000		95,110,000		98,444,000
Loans more than 90 days delinquent, still on accrual	427,000		427,000		3,000,000
Real estate owned/repossessed assets	86,400,000		86,400,000		110,386,000
Total Assets	$ 181,937,000		$ 181,937,000		$ 216,359,000