Loans, Allowance for Loan Losses and Credit Quality (Summary of Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 25,499	$ 27,690
Commercial and Industrial [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	3,195	3,699
Commercial Real Estate [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	8,027	7,856
Construction Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	304
Small Business [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	189	239
Residential Real Estate [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	7,510	8,795
Consumer Home Equity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	6,508	6,742
Consumer - Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 70	$ 55