| **Loans - Impaired Loans by Class (Details) - USD ($) $ in Thousands**           | 12 Months Ended |
|----------------------------------------------------------------------------------|-----------------|
||
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | $ 19,716        | $ 20,889 | $ 26,313 |
| Recorded Investment, With Related Allowance                                      | 7,867           | 8,642 | 9,549 |
| Balance of impaired loans                                                        | 27,583          | 29,531 | 35,862 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 21,853          | 22,947 | 29,077 |
| Unpaid Principal Balance, With Related Allowance                                 | 8,116           | 8,959 | 9,949 |
| Unpaid Principal Balance                                                         | 29,969          | 31,906 | 39,026 |
| Related Allowance                                                                | 974             | 754 | 1,803 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 19,605          | 22,808 | 26,926 |
| Average Recorded Investment, With Related Allowance                              | 8,612           | 9,890 | 11,478 |
| Average Recorded Investment                                                      | 28,217          | 32,698 | 38,404 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 781             | 839 | 1,078 |
| Recorded Interest Income, With Related Allowance                                 | 323             | 381 | 387 |
| Recorded Interest Income                                                         | 1,104           | 1,220 | 1,465 |
| Commercial | Real Estate                                                         |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 5,201           | 7,173 | 11,687 |
| Recorded Investment, With Related Allowance                                      | 4,820           | 3,544 | 1,617 |
| Balance of impaired loans                                                        | 10,021          | 10,717 | 13,304 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 5,614           | 7,496 | 12,423 |
| Unpaid Principal Balance, With Related Allowance                                 | 4,925           | 3,627 | 1,789 |
| Unpaid Principal Balance                                                         | 10,539          | 11,123 | 14,212 |
| Related Allowance                                                                | 505             | 89 | 346 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 6,252           | 8,990 | 11,080 |
| Average Recorded Investment, With Related Allowance                              | 4,153           | 3,066 | 3,040 |
| Average Recorded Investment                                                      | 10,405          | 12,056 | 14,120 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 220             | 301 | 488 |
| Recorded Interest Income, With Related Allowance                                 | 186             | 149 | 62 |
| Recorded Interest Income                                                         | 406             | 450 | 550 |
| Commercial | Construction                                                        |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 0               | 30 | 0 |
| Recorded Investment, With Related Allowance                                      | 763             | 996 | 1,380 |
| Balance of impaired loans                                                        | 763             | 1,026 | 1,380 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 0               | 30 | 0 |
| Unpaid Principal Balance, With Related Allowance                                 | 763             | 996 | 1,380 |
| Unpaid Principal Balance                                                         | 763             | 1,026 | 1,380 |
| Related Allowance                                                                | 100             | 302 | 413 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 32              | 3 | 30 |
| Average Recorded Investment, With Related Allowance                              | 816             | 1,153 | 1,279 |
| Average Recorded Investment                                                      | 848             | 1,156 | 1,309 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 0               | 1 | 0 |
| Recorded Interest Income, With Related Allowance                                 | 36              | 44 | 56 |
| Recorded Interest Income                                                         | 36              | 45 | 56 |
| Commercial | Other                                                               |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 1,671           | 1,163 | 2,616 |
| Recorded Investment, With Related Allowance                                      | 72              | 71 | 326 |
| Balance of impaired loans                                                        | 1,743           | 1,234 | 2,942 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 1,852           | 1,210 | 3,407 |
| Unpaid Principal Balance, With Related Allowance                                 | 72              | 77 | 338 |
| Unpaid Principal Balance                                                         | 1,924           | 1,287 | 3,745 |
| Related Allowance                                                                | 39              | 8 | 129 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 1,074           | 1,893 | 3,853 |
| Average Recorded Investment, With Related Allowance                              | 317             | 256 | 1,103 |
| Average Recorded Investment                                                      | 1,391           | 2,149 | 4,956 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 86              | 76 | 156 |
| Recorded Interest Income, With Related Allowance                                 | 0               | 5 | 13 |
| Recorded Interest Income                                                         | 86              | 81 | 169 |
| Municipal                                                                        |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 0               | 0 | 0 |
| Recorded Investment, With Related Allowance                                      | 0               | 0 | 0 |
| Balance of impaired loans                                                        | 0               | 0 | 0 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 0               | 0 | 0 |
| Unpaid Principal Balance, With Related Allowance                                 | 0               | 0 | 0 |
| Unpaid Principal Balance                                                         | 0               | 0 | 0 |
| Related Allowance                                                                | 0               | 0 | 0 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 0               | 0 | 0 |
| Average Recorded Investment, With Related Allowance                              | 0               | 0 | 0 |
| Average Recorded Investment                                                      | 0               | 0 | 0 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 0               | 0 | 0 |
| Recorded Interest Income, With Related Allowance                                 | 0               | 0 | 0 |
| Recorded Interest Income                                                         | 0               | 0 | 0 |
| Residential | Construction                                                       |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 0               | 0 | 0 |
| Recorded Investment, With Related Allowance                                      | 0               | 0 | 0 |
| Balance of impaired loans                                                        | 0               | 0 | 0 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 0               | 0 | 0 |
| Unpaid Principal Balance, With Related Allowance                                 | 0               | 0 | 0 |
| Unpaid Principal Balance                                                         | 0               | 0 | 0 |
| Related Allowance                                                                | 0               | 0 | 0 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 0               | 0 | 0 |
| Average Recorded Investment, With Related Allowance                              | 0               | 0 | 0 |
| Average Recorded Investment                                                      | 0               | 0 | 0 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 0               | 0 | 0 |
| Recorded Interest Income, With Related Allowance                                 | 0               | 0 | 0 |
| Recorded Interest Income                                                         | 0               | 0 | 0 |
| Residential | Term                                                               |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 11,483          | 11,122 | 10,820 |
| Recorded Investment, With Related Allowance                                      | 2,186           | 3,966 | 5,303 |
| Balance of impaired loans                                                        | 13,669          | 15,088 | 16,123 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 12,654          | 12,157 | 11,824 |
| Unpaid Principal Balance, With Related Allowance                                 | 2,328           | 4,193 | 5,513 |
| Unpaid Principal Balance                                                         | 14,982          | 16,350 | 17,337 |
| Related Allowance                                                                | 304             | 326 | 519 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 11,025          | 10,480 | 10,505 |
| Average Recorded Investment, With Related Allowance                              | 3,209           | 5,228 | 5,738 |
| Average Recorded Investment                                                      | 14,234          | 15,708 | 16,243 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 442             | 415 | 402 |
| Recorded Interest Income, With Related Allowance                                 | 101             | 180 | 239 |
| Recorded Interest Income                                                         | 543             | 595 | 641 |
| Home Equity LIne of Credit                                                       |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 1,361           | 1,401 | 1,164 |
| Recorded Investment, With Related Allowance                                      | 26              | 65 | 923 |
| Balance of impaired loans                                                        | 1,387           | 1,466 | 2,087 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 1,733           | 2,054 | 1,395 |
| Unpaid Principal Balance, With Related Allowance                                 | 28              | 66 | 929 |
| Unpaid Principal Balance                                                         | 1,761           | 2,120 | 2,324 |
| Related Allowance                                                                | 26              | 29 | 396 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 1,213           | 1,400 | 1,447 |
| Average Recorded Investment, With Related Allowance                              | 69              | 187 | 318 |
| Average Recorded Investment                                                      | 1,282           | 1,587 | 1,765 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 33              | 43 | 29 |
| Recorded Interest Income, With Related Allowance                                 | 0               | 3 | 17 |
| Recorded Interest Income                                                         | 33              | 46 | 46 |
| Consumer                                                                         |            |   |   |
| **Impaired Financing Receivable, Recorded Investment [Abstract]**                |            |   |   |
| Recorded Investment, No Related Allowance                                        | 0               | 0 | 26 |
| Recorded Investment, With Related Allowance                                      | 0               | 0 | 0 |
| Balance of impaired loans                                                        | 0               | 0 | 26 |
| **Impaired Financing Receivable, Unpaid Principal Balance [Abstract]**           |            |   |   |
| Unpaid Principal Balance, No Related Allowance                                   | 0               | 0 | 28 |
| Unpaid Principal Balance, With Related Allowance                                 | 0               | 0 | 0 |
| Unpaid Principal Balance                                                         | 0               | 0 | 28 |
| Related Allowance                                                                | 0               | 0 | 0 |
| **Impaired Financing Receivable, Average Recorded Investment [Abstract]**        |            |   |   |
| Average Recorded Investment, No Related Allowance                                | 9               | 42 | 11 |
| Average Recorded Investment, With Related Allowance                              | 48              | 0 | 0 |
| Average Recorded Investment                                                      | 57              | 42 | 11 |
| **Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]** |            |   |   |
| Recorded Interest Income, No Related Allowance                                   | 0               | 3 | 3 |
| Recorded Interest Income, With Related Allowance                                 | 0               | 0 | 0 |
| Recorded Interest Income                                                         | $ 0             | $ 3 | $ 3 |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
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Amount of allowance for credit losses related to recorded investment.
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Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.
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Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired.
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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.
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