Loans and Allowance for Loan Losses (Details 9) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	$ 719	$ 2,218
Loans Past Due Accruing Interest, 60-89 Days	177	1,048
Loans Past Due Accruing Interest, Over 90 Days	33	6
Loans Past Due Accruing Interest, Total	929	3,272
Loans on Non - Accrual	5,383	5,703
Loans Not Past Due or Non - Accrual	363,293	323,829
Total	369,605	332,804	309,524	333,079	335,310
Commercial [Member]
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	46	182
Loans Past Due Accruing Interest, 60-89 Days		120
Loans Past Due Accruing Interest, Over 90 Days		6
Loans Past Due Accruing Interest, Total	46	308
Loans on Non - Accrual	492	413
Loans Not Past Due or Non - Accrual	82,005	69,335
Total	82,543	70,056
Real estate - commercial [Member]
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	199	538
Loans Past Due Accruing Interest, 60-89 Days	62	144
Loans Past Due Accruing Interest, Over 90 Days
Loans Past Due Accruing Interest, Total	261	682
Loans on Non - Accrual	2,189	2,982
Loans Not Past Due or Non - Accrual	170,314	147,165
Total	172,764	150,829
Real estate - construction [Member]
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	10
Loans Past Due Accruing Interest, 60-89 Days
Loans Past Due Accruing Interest, Over 90 Days	26
Loans Past Due Accruing Interest, Total	36
Loans on Non - Accrual	269	231
Loans Not Past Due or Non - Accrual	16,497	12,248
Total	16,802	12,479
Consumer [Member]
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	22	22
Loans Past Due Accruing Interest, 60-89 Days	6	4
Loans Past Due Accruing Interest, Over 90 Days	7
Loans Past Due Accruing Interest, Total	35	26
Loans on Non - Accrual	16	29
Loans Not Past Due or Non - Accrual	8,298	8,112
Total	8,349	8,167
Real estate mortgage [Member]
Summary of the Aging of the Recorded Investment in Past Due and Nonaccrual Loans
Loans Past Due Accruing Interest, 30-59 Days	442	1,476
Loans Past Due Accruing Interest, 60-89 Days	109	780
Loans Past Due Accruing Interest, Over 90 Days
Loans Past Due Accruing Interest, Total	551	2,256
Loans on Non - Accrual	2,417	2,048
Loans Not Past Due or Non - Accrual	86,179	86,969
Total	$ 89,147	$ 91,273