Loans (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 729,167		$ 753,579
Allowance for loan losses	(11,438)	(10,943)	(10,379)	(9,627)	(9,507)	(9,723)
Net Loans	717,729		743,200
Change Amount	(24,412)
Change %	(3.20%)
Allowance for loan losses, Change Amount	(1,059)
Allowance for loan losses, Change %	10.20%
Net Loans, Change Amount	(25,471)
Net Loans, Change %	(3.40%)
Net unamortized deferred loan costs included in the loan balances	360		456
Unamortized deferred loan costs included in the loan balances	(109)		(129)
Loans pledged as collateral for borrowings and commitments from: FHLB	592,412		657,684
Loans pledged as collateral for borrowings and commitments from :Federal Reserve Bank	79,460		112,613
Total loans pledged as collateral	671,872		770,297
Residential Real Estate 1-4 Family Consumer First Liens [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	99,350		93,790
Change Amount	5,560
Change %	5.90%
Residential Real Estate 1-4 Family Consumer Junior Liens And Lines Of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	32,724		35,494
Change Amount	(2,770)
Change %	(7.80%)
Residential Real Estate 1-4 Family Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	132,074		129,284
Change Amount	2,790
Change %	2.20%
Residential Real Estate 1-4 Family Commercial first lien [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	57,063		60,809
Change Amount	(3,746)
Change %	(6.20%)
Residential Real Estate 1-4 Family Commercial junior liens and lines of credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	6,443		6,794
Change Amount	(351)
Change %	(5.20%)
Residential Real Estate 1-4 Family Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	63,506		67,603
Change Amount	(4,097)
Change %	(6.10%)
Residential Real Estate 1-4 Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	195,580		196,887
Change Amount	(1,307)
Change %	(0.70%)
Residential real estate- Construction Consumer purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,451		3,255
Change Amount	1,196
Change %	36.70%
Residential real estate- Construction Commercial purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	7,585		12,177
Change Amount	(4,592)
Change %	(37.70%)
Residential Real Estate - Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	12,036		15,432
Allowance for loan losses	(701)	(837)	(899)	(925)	(878)	(1,222)
Change Amount	(3,396)
Change %	(22.00%)
Commercial, Industrial And Agricultural Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	359,563		363,874
Allowance for loan losses	(6,730)	(6,682)	(6,450)	(5,839)	(5,792)	(5,257)
Change Amount	(4,311)
Change %	(1.20%)
Commercial, Industrial And Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	152,423		166,734
Allowance for loan losses	(2,202)	(1,972)	(1,620)	(1,564)	(1,388)	(1,651)
Change Amount	(14,311)
Change %	(8.60%)
Total Commercial, Industrial And Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	511,986		530,608
Change Amount	(18,622)
Change %	(3.50%)
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	9,565		10,652
Allowance for loan losses	(162)	(183)	(191)	(201)	(206)	(236)
Change Amount	$ (1,087)
Change %	(10.20%)