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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Feb. 01, 2021 $ / shares shares | Sep. 30, 2021 item | Dec. 31, 2022 USD ($) item segment $ / shares | Dec. 31, 2021 USD ($) $ / shares | Jan. 01, 2021 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Number of branch locations | item |  |  | 59 |  |
Share conversion ratio | 0.6480 |  | 1 |  |
Number of real estate investments dissolved | item |  | 2 |  |  |
Accrued interest related to debt securities reversed against interest income |  |  | $ 0 | $ 0 |
Non-accrual debt securities |  |  | 0 | 0 |
Collectively evaluated for impairment |  |  | 10,520,000,000 |  |
Individually evaluated for impairment |  |  | 47,600,000 |  |
Individually evaluated for impairment, allowance |  |  | 26,400,000 |  |
Retained earnings |  |  | 762,762,000 | $ 654,726,000 |
Collectively evaluated for impairment, allowance |  |  | $ 57,100,000 |  |
Merger agreement: |  |  |  |  |
Common stock, par value (in dollars per share) | $ / shares | $ 0.01 |  | $ 0.01 | $ 0.01 |
Common stock converted into right to receive shares (in shares) | shares | 0.6480 |  |  |  |
Preferred stock, Series A, par value (in dollars per share) | $ / shares | $ 0.01 |  | $ 0.01 | $ 0.01 |
Unrecognized tax benefits |  |  | $ 0 | $ 0 |
Number of Reportable Segments | segment |  |  | 1 |  |
Number of Operating Segments | segment |  |  | 1 |  |
Core deposits |  |  |  |  |
Merger agreement: |  |  |  |  |
Intangible Asset Useful Life |  |  | 10 years |  |
Cumulative Effect, CECL Adoption, Adjustment | Accounting Standards Update 2016-13 |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Decrease in allowance for credit losses |  |  | $ 3,900,000 |  |
Retained earnings |  |  |  |  | $ 1,700,000
Reserve for unfunded commitments |  |  | $ 1,400,000 |  |
Maximum | Buildings |  |  |  |  |
Merger agreement: |  |  |  |  |
Property Plant and Equipment Useful Life |  |  | 50 years |  |
Maximum | Furniture Fixtures And Equipment [Member] |  |  |  |  |
Merger agreement: |  |  |  |  |
Property Plant and Equipment Useful Life |  |  | 10 years |  |
Minimum | Buildings |  |  |  |  |
Merger agreement: |  |  |  |  |
Property Plant and Equipment Useful Life |  |  | 40 years |  |
Minimum | Furniture Fixtures And Equipment [Member] |  |  |  |  |
Merger agreement: |  |  |  |  |
Property Plant and Equipment Useful Life |  |  | 3 years |  |

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