Loans Allowance for Credit Losses and Credit Quality (Details 6) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Average Recorded Investment	$ 9,880	$ 8,142	$ 9,177	$ 4,028
Interest Income Recognized	75	88	361	145
Average Recorded Investment with No Related Allowance Recorded	1,457	3,544	1,410	1,867
Interest Income Recognized No Related Allowance Recorded	38	77	45	109
Average Recorded Investment with Related Allowance Recorded	8,423	4,598	7,767	2,161
Interest Income Recognized Related Allowance Recorded	37	11	316	36
Commercial [Member]
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Average Recorded Investment	1,284	1,438	1,278	946
Interest Income Recognized	34	22	54	35
Average Recorded Investment with No Related Allowance Recorded	434	976	302	600
Interest Income Recognized No Related Allowance Recorded	29	20	33	32
Average Recorded Investment with Related Allowance Recorded	850	462	976	346
Interest Income Recognized Related Allowance Recorded	5	2	21	3
Commercial real estate [Member]
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Average Recorded Investment	5,429	3,243	4,669	1,360
Interest Income Recognized	53	0	266	46
Average Recorded Investment with No Related Allowance Recorded	438	899	302	429
Interest Income Recognized No Related Allowance Recorded	6	0	6	30
Average Recorded Investment with Related Allowance Recorded	4,991	2,344	4,367	931
Interest Income Recognized Related Allowance Recorded	47	0	260	16
Residential real estate [Member]
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Average Recorded Investment	2,966	3,070	2,967	1,512
Interest Income Recognized	(16)	57	32	48
Average Recorded Investment with No Related Allowance Recorded	519	1,422	734	733
Interest Income Recognized No Related Allowance Recorded	3	49	5	36
Average Recorded Investment with Related Allowance Recorded	2,447	1,648	2,233	779
Interest Income Recognized Related Allowance Recorded	(19)	8	27	12
Consumer [Member]
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Average Recorded Investment	201	391	263	210
Interest Income Recognized	4	9	9	16
Average Recorded Investment with No Related Allowance Recorded	66	247	72	105
Interest Income Recognized No Related Allowance Recorded	0	8	1	11
Average Recorded Investment with Related Allowance Recorded	135	144	191	105
Interest Income Recognized Related Allowance Recorded	$ 4	$ 1	$ 8	$ 5

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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