Loans and Allowance for Loan Losses - Troubled Debt Restructured Loans (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 Loans	Dec. 31, 2011 Loans
Troubled Debt Restructurings
Total amount of troubled debt restructured loans outstanding	$ 23,700,000	$ 43,500,000
Allowance for troubled debt restructed loans	746,581	2,300,000
Amount of troubled debt restructured loans accruing interest	17,700,000	17,200,000
Number of Loans	35	43
Recorded Investment Prior to Modification	13,701,000	24,644,000
Recorded Investment After Modification	12,261,000	21,766,000
Number of troubled debt restructured loans with a payment default during the period	4,000	9
Recorded investment of troubled debt restructured loans with payment default during period	287,000	1,848,000
Below Market Rate
Troubled Debt Restructurings
Number of Loans	0	6
Recorded Investment Prior to Modification	0	5,918,000
Recorded Investment After Modification	0	5,491,000
Extended Payment Terms
Troubled Debt Restructurings
Number of Loans	32	29
Recorded Investment Prior to Modification	12,965,000	14,955,000
Recorded Investment After Modification	11,681,000	13,864,000
Number of troubled debt restructured loans with a payment default during the period	4,000	7
Recorded investment of troubled debt restructured loans with payment default during period	287,000	811,000
Principal Payment Reducation
Troubled Debt Restructurings
Number of Loans	3	8
Recorded Investment Prior to Modification	736,000	3,771,000
Recorded Investment After Modification	580,000	2,411,000
Number of troubled debt restructured loans with a payment default during the period	0	2
Recorded investment of troubled debt restructured loans with payment default during period	0	1,037,000
Real Estate Loans | Below Market Rate | Construction Loans
Troubled Debt Restructurings
Number of Loans	0	5
Recorded Investment Prior to Modification	0	5,768,000
Recorded Investment After Modification	0	5,341,000
Real Estate Loans | Below Market Rate | One to Four Family
Troubled Debt Restructurings
Number of Loans	0	1
Recorded Investment Prior to Modification	0	150,000
Recorded Investment After Modification	0	150,000
Real Estate Loans | Extended Payment Terms | Construction Loans
Troubled Debt Restructurings
Number of Loans	5	8
Recorded Investment Prior to Modification	1,231,000	2,704,000
Recorded Investment After Modification	872,000	2,696,000
Number of troubled debt restructured loans with a payment default during the period	0	1
Recorded investment of troubled debt restructured loans with payment default during period	0	221,000
Real Estate Loans | Extended Payment Terms | Owner Occupied
Troubled Debt Restructurings
Number of Loans	9	13
Recorded Investment Prior to Modification	2,443,000	10,445,000
Recorded Investment After Modification	2,379,000	9,983,000
Number of troubled debt restructured loans with a payment default during the period	1,000	2
Recorded investment of troubled debt restructured loans with payment default during period	93,000	124,000
Real Estate Loans | Extended Payment Terms | Non-owner Occupied
Troubled Debt Restructurings
Number of Loans	6	3
Recorded Investment Prior to Modification	5,329,000	1,133,000
Recorded Investment After Modification	4,990,000	536,000
Number of troubled debt restructured loans with a payment default during the period	1,000	0
Recorded investment of troubled debt restructured loans with payment default during period	0	0
Real Estate Loans | Extended Payment Terms | One to Four Family
Troubled Debt Restructurings
Number of Loans	4	2
Recorded Investment Prior to Modification	1,259,000	327,000
Recorded Investment After Modification	1,130,000	303,000
Number of troubled debt restructured loans with a payment default during the period	1,000	1
Recorded investment of troubled debt restructured loans with payment default during period	170,000	120,000
Real Estate Loans | Principal Payment Reducation | Construction Loans
Troubled Debt Restructurings
Number of Loans	0	4
Recorded Investment Prior to Modification	0	3,302,000
Recorded Investment After Modification	0	1,942,000
Number of troubled debt restructured loans with a payment default during the period	0	1
Recorded investment of troubled debt restructured loans with payment default during period	0	797,000
Real Estate Loans | Principal Payment Reducation | Owner Occupied
Troubled Debt Restructurings
Number of Loans	2	1
Recorded Investment Prior to Modification	571,000	240,000
Recorded Investment After Modification	571,000	240,000
Real Estate Loans | Principal Payment Reducation | Home Equity Lines of Credit
Troubled Debt Restructurings
Number of Loans	0	1
Recorded Investment Prior to Modification	0	165,000
Recorded Investment After Modification	0	165,000
Number of troubled debt restructured loans with a payment default during the period	0	1
Recorded investment of troubled debt restructured loans with payment default during period	0	240,000
Commercial | Extended Payment Terms
Troubled Debt Restructurings
Number of Loans	7	3
Recorded Investment Prior to Modification	2,676,000	346,000
Recorded Investment After Modification	2,286,000	346,000
Number of troubled debt restructured loans with a payment default during the period	0	3
Recorded investment of troubled debt restructured loans with payment default during period	0	346,000
Commercial | Principal Payment Reducation
Troubled Debt Restructurings
Number of Loans	0	2
Recorded Investment Prior to Modification	0	64,000
Recorded Investment After Modification	0	64,000
Consumer and other | Extended Payment Terms
Troubled Debt Restructurings
Number of Loans	1	0
Recorded Investment Prior to Modification	27,000	0
Recorded Investment After Modification	24,000	0
Number of troubled debt restructured loans with a payment default during the period	1,000	0
Recorded investment of troubled debt restructured loans with payment default during period	24,000	0
Consumer and other | Principal Payment Reducation
Troubled Debt Restructurings
Number of Loans	1	0
Recorded Investment Prior to Modification	165,000	0
Recorded Investment After Modification	$ 9,000	$ 0