Loans, Allowance for Loan Losses and Credit Quality (Impaired Loans by Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 2,318	$ 2,416	$ 2,942
Related Allowance	2,318	2,416
Impaired Financing Receivable, Recorded Investment, Total	62,880	58,035
Impaired Financing Receivable, Unpaid Principal Balance	66,469	61,887
WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	34,675	26,936
Unpaid Principal Balance	36,804	28,535
WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	28,205	31,099
Unpaid Principal Balance	29,665	33,352
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	308	412	647
Commercial and Industrial [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	3,489	3,005
Unpaid Principal Balance	4,139	3,278
Commercial and Industrial [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	2,868	1,649
Unpaid Principal Balance	2,887	1,859
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	265	197	369
Commercial Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	21,323	15,982
Unpaid Principal Balance	22,615	17,164
Commercial Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	10,839	14,747
Unpaid Principal Balance	10,974	15,514
Commercial Construction [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Commercial Construction [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	311	311
Unpaid Principal Balance	311	311
Small Business [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5	7	109
Small Business [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	680	692
Unpaid Principal Balance	721	718
Small Business [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	347	396
Unpaid Principal Balance	372	458
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,453	1,500	1,641
Residential Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	3,464	2,439
Unpaid Principal Balance	3,556	2,502
Residential Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	12,363	12,616
Unpaid Principal Balance	13,517	13,727
Consumer - Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	253	262	114
Consumer - Home Equity [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	4,731	4,169
Unpaid Principal Balance	4,781	4,221
Consumer - Home Equity [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	1,283	1,161
Unpaid Principal Balance	1,410	1,264
Consumer - Other [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	34	38	62
Consumer - Other [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	677	338
Unpaid Principal Balance	681	341
Consumer - Other [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	505	530
Unpaid Principal Balance	$ 505	$ 530

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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