Loans Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 14,603	$ 15,053	$ 15,298	$ 15,003
Charge-offs	(92)	(136)	(982)	(433)
Recoveries	67	54	162	121
Provision	100	240	200	520
Allowance for Loan Losses, Ending Balance	14,678	15,211	14,678	15,211
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	765	0	765	853
Allowance for loan losses - Loans Collectively Evaluated for Impairment	14,678	14,446	14,678	14,446	14,445
Ending Loan Balance - Individually Evaluated for Impairment	2,776	5,027	2,776	5,027	5,253
Ending Loan Balance - Collectively Evaluated for Impairment	1,201,958	1,141,614	1,201,958	1,141,614	1,167,088
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	1,619	1,834	2,344	1,927
Charge-offs	(15)	(10)	(788)	(15)
Recoveries	36	1	40	3
Provision	(88)	273	(44)	183
Allowance for Loan Losses, Ending Balance	1,552	2,098	1,552	2,098
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	765	0	765	853
Allowance for loan losses - Loans Collectively Evaluated for Impairment	1,552	1,333	1,552	1,333	1,491
Ending Loan Balance - Individually Evaluated for Impairment	33	1,699	33	1,699	1,432
Ending Loan Balance - Collectively Evaluated for Impairment	87,516	99,595	87,516	99,595	104,104
Commercial Construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	612	661	601	602
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	34	(133)	45	(74)
Allowance for Loan Losses, Ending Balance	646	528	646	528
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	646	528	646	528	601
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	30,980	17,628	30,980	17,628	29,149
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	3,379	3,297	3,050	3,136
Charge-offs	0	0	(11)	(167)
Recoveries	0	0	0	0
Provision	(86)	(2)	254	326
Allowance for Loan Losses, Ending Balance	3,293	3,295	3,293	3,295
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	3,293	3,295	3,293	3,295	3,050
Ending Loan Balance - Individually Evaluated for Impairment	1,481	1,625	1,481	1,625	2,528
Ending Loan Balance - Collectively Evaluated for Impairment	258,318	234,236	258,318	234,236	242,649
Other Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	308	352	304	350
Charge-offs	(5)	(23)	(13)	(42)
Recoveries	0	3	0	9
Provision	(4)	23	8	38
Allowance for Loan Losses, Ending Balance	299	355	299	355
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	299	355	299	355	304
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	7,456	6,543	7,456	6,543	6,684
Automobile [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	4,294	4,530	4,536	4,496
Charge-offs	(72)	(70)	(170)	(176)
Recoveries	31	50	122	109
Provision	104	61	(131)	142
Allowance for Loan Losses, Ending Balance	4,357	4,571	4,357	4,571
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	4,357	4,571	4,357	4,571	4,536
Ending Loan Balance - Individually Evaluated for Impairment	184	213	184	213	203
Ending Loan Balance - Collectively Evaluated for Impairment	374,876	333,885	374,876	333,885	348,897
Residential [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	3,392	3,300	3,405	3,414
Charge-offs	0	(33)	0	(33)
Recoveries	0	0	0	0
Provision	16	184	3	70
Allowance for Loan Losses, Ending Balance	3,408	3,451	3,408	3,451
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	3,408	3,451	3,408	3,451	3,405
Ending Loan Balance - Individually Evaluated for Impairment	1,078	1,490	1,078	1,490	1,090
Ending Loan Balance - Collectively Evaluated for Impairment	442,812	449,727	442,812	449,727	435,605
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	999	1,079	1,058	1,078
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	124	(166)	65	(165)
Allowance for Loan Losses, Ending Balance	1,123	913	1,123	913
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	1,123	913	1,123	913	1,058
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	$ 0	$ 0	$ 0	$ 0	$ 0