Loans, Allowance for Loan Losses, and Credit Quality Loans Modified in a Troubled Debt Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Financing Receivable, Modifications [Line Items]
Number of Loans	69	93	130	188
Recorded Investment	$ 5,014	$ 15,891	$ 17,415	$ 27,641
Unpaid Principal Balance	5,608	17,189	22,733	31,014
Commercial and Industrial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	3	25	11	43
Recorded Investment	526	4,323	3,889	6,401
Unpaid Principal Balance	534	4,414	7,736	8,074
Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	7	5	10
Recorded Investment	894	4,086	6,096	6,270
Unpaid Principal Balance	894	4,194	6,652	6,388
Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	3	1	8
Recorded Investment	0	1,801	493	3,822
Unpaid Principal Balance	0	1,948	508	4,029
Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	2	1	7
Recorded Investment	6	51	6	2,004
Unpaid Principal Balance	6	80	6	2,057
Home Equity Port Folio Segments [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	35	29	62	62
Recorded Investment	1,630	2,114	2,476	3,580
Unpaid Principal Balance	1,723	2,640	2,693	4,192
Installment and Credit Cards [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	1	2	2
Recorded Investment	16	34	25	199
Unpaid Principal Balance	16	34	35	202
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	28	26	48	56
Recorded Investment	1,942	3,482	4,430	5,365
Unpaid Principal Balance	$ 2,435	$ 3,879	$ 5,103	$ 6,072