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Summary of Significant Accounting Policies (Details Textual) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 01, 2021 | Dec. 31, 2020 USD ($) Segment Location County_Economy | Dec. 31, 2019 USD ($) Reporting Segment | Jan. 01, 2019 USD ($) | Dec. 31, 2018 USD ($)
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Number of locations served by bank | Location |  | 40 |  |  |
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 |  | 68.30% |  |  |
Impairment on commercial and commercial real estate loans, threshold amount |  | $ 400,000 |  |  |
Impairment on consumer and residential real estate loans, threshold amount |  | 250,000 |  |  |
Valuation allowance impairment against servicing assets |  | 0 | $ 0 |  | $ 0
Other real estate owned |  | 0 | 19,000 |  |
Restricted stock |  | $ 14,600,000 | 11,700,000 |  |
Recognized tax amount |  | 50.00% |  |  |
Charge accrued relating to pending settlement of legal contingency |  |  | 505,000 |  |
Deposits with Federal Reserve Bank |  | $ 201,000,000.0 | $ 36,100,000 |  |
Operating segments of business | Segment |  | 2 | 3 |  |
ASU 2017-04 |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] |  | true |  |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date |  | Jan. 01, 2020 |  |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] |  | true |  |  |
ASU 2016-02 |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] |  | true |  |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date |  | Jan. 01, 2019 |  |  |
Capitalization of leases as an asset |  |  |  | $ 3,600,000 |
Minimum | ASU 2016-13 | Subsequent Event |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Increase in percentage of allowance for loan losses | 5.00% |  |  |  |
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 | ASU 2016-13 | Subsequent Event |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Increase in percentage of allowance for loan losses | 10.00% |  |  |  |
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 |  | 1 |  |  |
NAI |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |
Number of reporting units | Reporting |  |  | 1 |  |
Number of reportable segments | Segment |  |  | 1 |  |

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