Loans and Allowance for Loan Losses (Details 5) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Loans by credit quality indicators
Total loans	$ 1,022,956,000	$ 1,041,189,000	$ 1,051,674,000
Commercial and Industrial [Member]
Loans by credit quality indicators
Total loans	272,890,000	285,322,000
Commercial and Industrial [Member] | Grades 1-4 [Member]
Loans by credit quality indicators
Total loans	190,314,000	180,314,000
Commercial and Industrial [Member] | Grades 5-7 [Member]
Loans by credit quality indicators
Total loans	79,038,000	101,832,000
Commercial and Industrial [Member] | Grades 8-9 [Member]
Loans by credit quality indicators
Total loans	3,538,000	3,176,000
Commercial Vacant Land, Land Development, and Residential Construction [Member]
Loans by credit quality indicators
Total loans	45,174,000	48,099,000
Commercial Vacant Land, Land Development, and Residential Construction [Member] | Grades 1-4 [Member]
Loans by credit quality indicators
Total loans	8,065,000	6,526,000
Commercial Vacant Land, Land Development, and Residential Construction [Member] | Grades 5-7 [Member]
Loans by credit quality indicators
Total loans	33,858,000	37,697,000
Commercial Vacant Land, Land Development, and Residential Construction [Member] | Grades 8-9 [Member]
Loans by credit quality indicators
Total loans	3,251,000	3,876,000
Commercial Real Estate - Owner Occupied [Member]
Loans by credit quality indicators
Total loans	253,089,000	259,277,000
Commercial Real Estate - Owner Occupied [Member] | Grades 1-4 [Member]
Loans by credit quality indicators
Total loans	148,122,000	150,467,000
Commercial Real Estate - Owner Occupied [Member] | Grades 5-7 [Member]
Loans by credit quality indicators
Total loans	100,606,000	102,988,000
Commercial Real Estate - Owner Occupied [Member] | Grades 8-9 [Member]
Loans by credit quality indicators
Total loans	4,361,000	5,822,000
Commercial Real Estate - Non-Owner Occupied [Member]
Loans by credit quality indicators
Total loans	327,776,000	324,886,000
Commercial Real Estate - Non-Owner Occupied [Member] | Grades 1-4 [Member]
Loans by credit quality indicators
Total loans	166,374,000	154,127,000
Commercial Real Estate - Non-Owner Occupied [Member] | Grades 5-7 [Member]
Loans by credit quality indicators
Total loans	124,228,000	128,041,000
Commercial Real Estate - Non-Owner Occupied [Member] | Grades 8-9 [Member]
Loans by credit quality indicators
Total loans	37,174,000	42,718,000
Commercial Real Estate - Multi-Family and Residential Rental [Member]
Loans by credit quality indicators
Total loans	50,035,000	50,922,000
Commercial Real Estate - Multi-Family and Residential Rental [Member] | Grades 1-4 [Member]
Loans by credit quality indicators
Total loans	23,568,000	24,015,000
Commercial Real Estate - Multi-Family and Residential Rental [Member] | Grades 5-7 [Member]
Loans by credit quality indicators
Total loans	22,613,000	22,082,000
Commercial Real Estate - Multi-Family and Residential Rental [Member] | Grades 8-9 [Member]
Loans by credit quality indicators
Total loans	3,854,000	4,825,000
Retail home equity and other [Member]
Loans by credit quality indicators
Total loans	38,257,000	38,917,000
Retail 1-4 family mortgages [Member]
Loans by credit quality indicators
Total loans	$ 35,735,000	$ 33,766,000