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Significant Accounting Policies (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) segment banking_center | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Accounting Policies [Abstract] |  |  |
Number of banking centers | banking_center | 44 |  |
Number of segments | segment | 1 |  |
Equity investments | $ 15,700,000 | $ 12,100,000 |
Impairment loss |  | 0 |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
OREO | 1,500,000 | 1,600,000 |
Penalties and related interest | 0 | 0 | $ 0
Other Investments | 21,400,000 | 15,700,000 |
Investments in tax credit entities | $ 11,100,000 | $ 7,600,000 |
Tax Credit Entity |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
General partner ownership interest | 0.10% |  |
Buildings and improvements | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful lives | 35 years |  |
Buildings and improvements | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful lives | 39 years |  |
Furniture, fixtures and equipment | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful lives | 3 years |  |
Furniture, fixtures and equipment | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful lives | 7 years |  |

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