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Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) Contract | Dec. 31, 2014 USD ($) Contract
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 89 | 87
Pre-modification outstanding recorded investment | $ 7,155 | $ 6,993
Post-modification outstanding recorded investment | $ 6,703 | $ 5,547
Number of contracts, subsequent default | Contract | 7 | 13
Outstanding recorded investment, subsequent default | $ 552 | $ 732
Commercial Loans [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 2 | 3
Pre-modification outstanding recorded investment | $ 406 | $ 920
Post-modification outstanding recorded investment | $ 357 | $ 842
Commercial Loans [Member] | Commercial [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 1 |
Pre-modification outstanding recorded investment | $ 186 |
Post-modification outstanding recorded investment | $ 186 |
Commercial Loans [Member] | Business Banking [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 1 | 3
Pre-modification outstanding recorded investment | $ 220 | $ 920
Post-modification outstanding recorded investment | $ 171 | $ 842
Consumer Loans [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 50 | 57
Pre-modification outstanding recorded investment | $ 3,664 | $ 3,356
Post-modification outstanding recorded investment | $ 3,261 | $ 2,617
Number of contracts, subsequent default | Contract | 4 | 7
Outstanding recorded investment, subsequent default | $ 344 | $ 303
Consumer Loans [Member] | Indirect [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract |  | 1
Pre-modification outstanding recorded investment |  | $ 34
Post-modification outstanding recorded investment |  | $ 18
Number of contracts, subsequent default | Contract | 0 | 1
Outstanding recorded investment, subsequent default | $ 0 | $ 34
Consumer Loans [Member] | Home Equity [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 50 | 56
Pre-modification outstanding recorded investment | $ 3,664 | $ 3,322
Post-modification outstanding recorded investment | $ 3,261 | $ 2,599
Number of contracts, subsequent default | Contract | 4 | 6
Outstanding recorded investment, subsequent default | $ 344 | $ 269
Residential Real Estate Mortgages [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 37 | 27
Pre-modification outstanding recorded investment | $ 3,085 | $ 2,717
Post-modification outstanding recorded investment | $ 3,085 | $ 2,088
Number of contracts, subsequent default | Contract | 3 | 6
Outstanding recorded investment, subsequent default | $ 208 | $ 429

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