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Summary of Significant Accounting Policies (Details Textual) | 12 Months Ended
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Dec. 31, 2017 USD ($) Location County_Economy Segment | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |
Number of locations served by bank | Location | 39 |  |
Purchased and sold period of federal fund | 1 day |  |
Delinquent period of loans after which interest income is discontinued | 90 days |  |
Number of county economy from which credit risk exposure effected | County_Economy | 9 |  |
Percentage of portfolio loans secured by real estate | 69.80% |  |
Impairment on loan | $ 750,000 |  |
Valuation allowance impairment against servicing assets | 0 | $ 0 | $ 0
Other real estate owned | 171,000 | 482,000 |
Restricted stock | $ 10,500,000 | 9,600,000 |
Recognized tax amount | 50.00% |  |
Deposits with Federal Reserve Bank | $ 30,000,000 | 16,400,000 |
Operating segments of business | Segment | 3 |  |
Capitalization of leases as an asset | $ 2,900,000 |  |
Accumulated Other Comprehensive Income |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Reclassification from accumulated other comprehensive income to retained earnings resulted from early adoption of ASU 2018-02 | 106,000 | 0 | 0
Retained Earnings |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Reclassification from accumulated other comprehensive income to retained earnings resulted from early adoption of ASU 2018-02 | $ (106,000) | 0 | $ 0
Minimum | Core Deposits |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Intangible assets amortized period | 7 years |  |
Minimum | Customer Relationships |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Intangible assets amortized period | 13 years |  |
Maximum | Core Deposits |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Intangible assets amortized period | 8 years |  |
Maximum | Customer Relationships |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Intangible assets amortized period | 15 years |  |
Buildings | Minimum |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Range of buildings and furniture depreciated | 5 years |  |
Buildings | Maximum |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Range of buildings and furniture depreciated | 40 years |  |
Furniture Fixtures and Equipment | Minimum |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Range of buildings and furniture depreciated | 3 years |  |
Furniture Fixtures and Equipment | Maximum |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Range of buildings and furniture depreciated | 10 years |  |
Mortgage Servicing Rights |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |
Valuation allowance impairment against servicing assets | $ 0 | $ 0 |
Residential Real Estate |  |  |
Summary of Significant Accounting Policies (Textual) [Abstract] |  |  |
Loan financing period | 15 years |  |
Southwestern Pennsylvania |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |
Number of locations served by bank | Location | 2 |  |

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