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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) segment | Jan. 01, 2021 USD ($) | Jan. 01, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Summary Of Accounting Policies [Line Items] |  |  |  |  |  |
Non-accrual debt securities | $ 0 |  |  |  |  |
Accrued interest related to debt securities | $ 0 |  |  |  |  |
Reasonable and supportable forecast, period | 2 years |  |  |  |  |
Income Taxes |  |  |  |  |  |
Unrecognized Tax Benefits | $ 0 |  |  | $ 0 |  |
Dividend Restriction |  |  |  |  |  |
Period from which net retained earnings are available for dividend payment from the Bank to the Parent Company | 2 years |  |  |  |  |
Cash dividends paid to the Company | $ 26,500 |  |  |  |  |
Segment Reporting |  |  |  |  |  |
Number of reportable operating segment | segment | 1 |  |  |  |  |
Standards Effective in 2020 |  |  |  |  |  |
Allowance for credit losses | $ 44,200 |  |  | 32,786 | $ 31,418 | $ 31,707
Retained earnings | 172,075 |  |  | $ 150,703 |  |
Forecast |  |  |  |  |  |
Dividend Restriction |  |  |  |  |  |
Dividends from Bank to the Company, available amount |  | $ 49,800 |  |  |  |
ASU 2016-13 | Effect of adoption |  |  |  |  |  |
Standards Effective in 2020 |  |  |  |  |  |
Allowance for credit losses | 1,625 |  | $ 1,600 |  |  |
Reserve for unfunded commitments |  |  | 500 |  |  |
Retained earnings | $ 1,500 |  | $ 0 |  |  |
Core deposit intangibles |  |  |  |  |  |
Summary Of Accounting Policies [Line Items] |  |  |  |  |  |
Core deposit intangible assets, useful life (in years) | 10 years |  |  |  |  |
Buildings |  |  |  |  |  |
Summary Of Accounting Policies [Line Items] |  |  |  |  |  |
Useful life | 50 years |  |  |  |  |
Equipment, computer hardware and software and furniture and fixtures | Minimum |  |  |  |  |  |
Summary Of Accounting Policies [Line Items] |  |  |  |  |  |
Useful life | 2 years |  |  |  |  |
Equipment, computer hardware and software and furniture and fixtures | Maximum |  |  |  |  |  |
Summary Of Accounting Policies [Line Items] |  |  |  |  |  |
Useful life | 10 years |  |  |  |  |

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