Loans and Allowance for Loan Losses (Details 2) (USD $)	Sep. 30, 2012	Dec. 31, 2011
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	$ 24,782,000	$ 45,074,000
Commercial and industrial [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	3,870,000	5,916,000
Vacant land, land development, and residential construction [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	2,850,000	3,448,000
Real estate - owner occupied [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	3,074,000	6,635,000
Real estate - non-owner occupied [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	11,157,000	24,169,000
Real estate - multi-family and residential rental [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	1,754,000	2,532,000
Total commercial [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	22,705,000	42,700,000
Retail home equity and other [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	733,000	1,013,000
Retail 1-4 family mortgages [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	1,344,000	1,361,000
Total retail [Member]
Recorded principal balance of nonaccrual loans, including troubled debt restructurings
Nonaccrual loans	$ 2,077,000	$ 2,374,000