| **Allowance for Loan Losses - Activity by Class (Details) - USD ($) $ in Thousands** | 3 Months Ended | 12 Months Ended |
|--------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | $ 9,916 |   |   |   | $ 10,344 | $ 9,916 | $ 10,344 | $ 11,514 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 1,721 | 2,373 | 3,495 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 343 | 395 | 1,175 |
| Provision for loan losses                                                            | $ 475          | $ 375           | $ 375 | 375 | $ 450 | $ 200 | $ 400 | 500 | 1,600 | 1,550 | 1,150 |
| Ending balance                                                                       | 10,138         |            |   |   | 9,916 |   |   |   | 10,138 | 9,916 | 10,344 |
| Ending balance specifically evaluated for impairment                                 | 974            |            |   |   | 754 |   |   |   | 974 | 754 | 1,803 |
| Ending balance collectively evaluated for impairment                                 | 9,164          |            |   |   | 9,162 |   |   |   | 9,164 | 9,162 | 8,541 |
| Loans                                                                                | 1,071,526      |            |   |   | 988,638 |   |   |   | 1,071,526 | 988,638 | 917,564 |
| Ending balance specifically evaluated for impairment                                 | 27,583         |            |   |   | 29,531 |   |   |   | 27,583 | 29,531 | 35,862 |
| Ending balance collectively evaluated for impairment                                 | 1,043,943      |            |   |   | 959,107 |   |   |   | 1,043,943 | 959,107 | 881,702 |
| Commercial | Real Estate                                                             |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 3,120 |   |   |   | 3,532 | 3,120 | 3,532 | 4,602 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 294 | 280 | 1,205 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 0 | 2 | 144 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 1,162 | (134) | (9) |
| Ending balance                                                                       | 3,988          |            |   |   | 3,120 |   |   |   | 3,988 | 3,120 | 3,532 |
| Ending balance specifically evaluated for impairment                                 | 505            |            |   |   | 89 |   |   |   | 505 | 89 | 346 |
| Ending balance collectively evaluated for impairment                                 | 3,483          |            |   |   | 3,031 |   |   |   | 3,483 | 3,031 | 3,186 |
| Loans                                                                                | 302,506        |            |   |   | 269,462 |   |   |   | 302,506 | 269,462 | 242,311 |
| Ending balance specifically evaluated for impairment                                 | 10,021         |            |   |   | 10,717 |   |   |   | 10,021 | 10,717 | 13,304 |
| Ending balance collectively evaluated for impairment                                 | 292,485        |            |   |   | 258,745 |   |   |   | 292,485 | 258,745 | 229,007 |
| Commercial | Construction                                                            |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 580 |   |   |   | 823 | 580 | 823 | 575 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 75 | 9 | 0 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 8 | 1 | 0 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | (117) | (235) | 248 |
| Ending balance                                                                       | 396            |            |   |   | 580 |   |   |   | 396 | 580 | 823 |
| Ending balance specifically evaluated for impairment                                 | 100            |            |   |   | 302 |   |   |   | 100 | 302 | 413 |
| Ending balance collectively evaluated for impairment                                 | 296            |            |   |   | 278 |   |   |   | 296 | 278 | 410 |
| Loans                                                                                | 25,406         |            |   |   | 24,881 |   |   |   | 25,406 | 24,881 | 30,932 |
| Ending balance specifically evaluated for impairment                                 | 763            |            |   |   | 1,026 |   |   |   | 763 | 1,026 | 1,380 |
| Ending balance collectively evaluated for impairment                                 | 24,643         |            |   |   | 23,855 |   |   |   | 24,643 | 23,855 | 29,552 |
| Commercial | Other                                                                   |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 1,452 |   |   |   | 1,505 | 1,452 | 1,505 | 2,276 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 376 | 732 | 989 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 129 | 88 | 758 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 575 | 591 | (540) |
| Ending balance                                                                       | 1,780          |            |   |   | 1,452 |   |   |   | 1,780 | 1,452 | 1,505 |
| Ending balance specifically evaluated for impairment                                 | 39             |            |   |   | 8 |   |   |   | 39 | 8 | 129 |
| Ending balance collectively evaluated for impairment                                 | 1,741          |            |   |   | 1,444 |   |   |   | 1,741 | 1,444 | 1,376 |
| Loans                                                                                | 150,769        |            |   |   | 128,341 |   |   |   | 150,769 | 128,341 | 104,531 |
| Ending balance specifically evaluated for impairment                                 | 1,743          |            |   |   | 1,234 |   |   |   | 1,743 | 1,234 | 2,942 |
| Ending balance collectively evaluated for impairment                                 | 149,026        |            |   |   | 127,107 |   |   |   | 149,026 | 127,107 | 101,589 |
| Municipal                                                                            |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 17 |   |   |   | 15 | 17 | 15 | 15 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 0 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 0 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 1 | 2 | 0 |
| Ending balance                                                                       | 18             |            |   |   | 17 |   |   |   | 18 | 17 | 15 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 18             |            |   |   | 17 |   |   |   | 18 | 17 | 15 |
| Loans                                                                                | 27,056         |            |   |   | 19,751 |   |   |   | 27,056 | 19,751 | 20,424 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 27,056         |            |   |   | 19,751 |   |   |   | 27,056 | 19,751 | 20,424 |
| Residential | Construction                                                           |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 24 |   |   |   | 20 | 24 | 20 | 21 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 0 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 25 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 20 | 4 | (26) |
| Ending balance                                                                       | 44             |            |   |   | 24 |   |   |   | 44 | 24 | 20 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 44             |            |   |   | 24 |   |   |   | 44 | 24 | 20 |
| Loans                                                                                | 18,303         |            |   |   | 8,451 |   |   |   | 18,303 | 8,451 | 12,160 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 18,303         |            |   |   | 8,451 |   |   |   | 18,303 | 8,451 | 12,160 |
| Residential | Term                                                                   |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 1,391 |   |   |   | 1,185 | 1,391 | 1,185 | 1,099 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 379 | 420 | 699 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 93 | 152 | 36 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 183 | 474 | 749 |
| Ending balance                                                                       | 1,288          |            |   |   | 1,391 |   |   |   | 1,288 | 1,391 | 1,185 |
| Ending balance specifically evaluated for impairment                                 | 304            |            |   |   | 326 |   |   |   | 304 | 326 | 519 |
| Ending balance collectively evaluated for impairment                                 | 984            |            |   |   | 1,065 |   |   |   | 984 | 1,065 | 666 |
| Loans                                                                                | 411,469        |            |   |   | 403,030 |   |   |   | 411,469 | 403,030 | 384,032 |
| Ending balance specifically evaluated for impairment                                 | 13,669         |            |   |   | 15,088 |   |   |   | 13,669 | 15,088 | 16,123 |
| Ending balance collectively evaluated for impairment                                 | 397,800        |            |   |   | 387,942 |   |   |   | 397,800 | 387,942 | 367,909 |
| Home Equity LIne of Credit                                                           |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 893 |   |   |   | 1,060 | 893 | 1,060 | 675 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 147 | 582 | 153 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 5 | 31 | 16 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 56 | 384 | 522 |
| Ending balance                                                                       | 807            |            |   |   | 893 |   |   |   | 807 | 893 | 1,060 |
| Ending balance specifically evaluated for impairment                                 | 26             |            |   |   | 29 |   |   |   | 26 | 29 | 396 |
| Ending balance collectively evaluated for impairment                                 | 781            |            |   |   | 864 |   |   |   | 781 | 864 | 664 |
| Loans                                                                                | 110,907        |            |   |   | 110,202 |   |   |   | 110,907 | 110,202 | 103,521 |
| Ending balance specifically evaluated for impairment                                 | 1,387          |            |   |   | 1,466 |   |   |   | 1,387 | 1,466 | 2,087 |
| Ending balance collectively evaluated for impairment                                 | 109,520        |            |   |   | 108,736 |   |   |   | 109,520 | 108,736 | 101,434 |
| Consumer                                                                             |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | 566 |   |   |   | 542 | 566 | 542 | 573 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 450 | 350 | 449 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 108 | 121 | 196 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | 335 | 253 | 222 |
| Ending balance                                                                       | 559            |            |   |   | 566 |   |   |   | 559 | 566 | 542 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 559            |            |   |   | 566 |   |   |   | 559 | 566 | 542 |
| Loans                                                                                | 25,110         |            |   |   | 24,520 |   |   |   | 25,110 | 24,520 | 19,653 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 26 |
| Ending balance collectively evaluated for impairment                                 | 25,110         |            |   |   | 24,520 |   |   |   | 25,110 | 24,520 | 19,627 |
| Unallocated                                                                          |           |            |   |   |   |   |   |   |   |   |   |
| **Allowance for Loan and Lease Losses [Roll Forward]**                               |           |            |   |   |   |   |   |   |   |   |   |
| Beginning balance                                                                    |           |            |   | $ 1,873 |   |   |   | $ 1,662 | 1,873 | 1,662 | 1,678 |
| Chargeoffs                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 0 |
| Recoveries                                                                           |           |            |   |   |   |   |   |   | 0 | 0 | 0 |
| Provision for loan losses                                                            |           |            |   |   |   |   |   |   | (615) | 211 | (16) |
| Ending balance                                                                       | 1,258          |            |   |   | 1,873 |   |   |   | 1,258 | 1,873 | 1,662 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | 1,258          |            |   |   | 1,873 |   |   |   | 1,258 | 1,873 | 1,662 |
| Loans                                                                                | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance specifically evaluated for impairment                                 | 0              |            |   |   | 0 |   |   |   | 0 | 0 | 0 |
| Ending balance collectively evaluated for impairment                                 | $ 0            |            |   |   | $ 0 |   |   |   | $ 0 | $ 0 | $ 0 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were collectively evaluated for impairment.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were individually evaluated for impairment.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related to estimated loss from loan and lease transactions.
+ References
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| X                                                                                                                                                                              |
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| X                                                                                                                                                                                     |
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