| **Summary of Significant Accounting Policies (Details) (USD $)In Thousands, unless otherwise specified** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------|-----------------|
||
| **Business Acquisition [Line Items]**                                                                    |            |   |   |
| Amortization of identified intangibles                                                                   | $ 326           | $ 283 | $ 283 |
| Core Deposits                                                                                            |            |   |   |
| **Business Acquisition [Line Items]**                                                                    |            |   |   |
| Amortization of identified intangibles                                                                   | 43              |   |   |
| Bank Acquisitions From Camden National Bank | Core Deposits                                              |            |   |   |
| **Business Acquisition [Line Items]**                                                                    |            |   |   |
| Finite lived intangible asset, amortization (in years)                                                   | 10 years        |   |   |
| Amortization of identified intangibles                                                                   | 43              |   |   |
| Amortization of Intangible Assets, Yearly Expense till Fully Amortized                                   | 43              |   |   |
| FNB Bankshares | Core Deposits                                                                           |            |   |   |
| **Business Acquisition [Line Items]**                                                                    |            |   |   |
| Finite lived intangible asset, amortization (in years)                                                   | 10 years        |   |   |
| Amortization of identified intangibles                                                                   | 283             | 283 | 283 |
| Amortization of Intangible Assets, Yearly Expense till Fully Amortized                                   | $ 283           |   |   |

| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortization of Intangible Assets, Yearly Expense till Fully Amortized
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
+ References
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| X                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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