Loans, Allowance for Loan Losses, and Credit Quality Loans Modified in a Troubled Debt Restructuring (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Number of Contracts	278	413
Recorded Investment	$ 64,052	$ 59,599
Unpaid Principal Balance	71,319	68,950
Commercial and Industrial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	48	85
Recorded Investment	11,833	12,827
Unpaid Principal Balance	14,543	15,834
Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	12	27
Recorded Investment	8,823	11,978
Unpaid Principal Balance	9,035	12,766
Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	25	25
Recorded Investment	26,480	12,379
Unpaid Principal Balance	28,516	13,569
Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	9	31
Recorded Investment	1,822	2,955
Unpaid Principal Balance	1,961	3,549
Home Equity Portfolio Segments [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	88	111
Recorded Investment	4,642	4,870
Unpaid Principal Balance	4,958	6,143
Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	13
Recorded Investment	193	298
Unpaid Principal Balance	200	302
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	93	121
Recorded Investment	10,259	14,292
Unpaid Principal Balance	$ 12,106	$ 16,787