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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
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New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Stockholders' equity |  | $ (177,341,000) |  | $ (166,388,000) |  | $ (185,510,000) | $ (211,455,000)
Allowance for credit losses |  | 20,075,000 | [1] | 19,659,000 | [1] | 19,928,000 | 21,025,000
Unfunded Loan Commitment |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  | 1,048,000 |  | 0 |  | 0 | 0
Commercial Mortgages |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  | 10,983,000 |  | 11,576,000 |  | 12,964,000 | 13,556,000
Consumer Loans |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  | 3,147,000 |  | 2,865,000 |  | 1,875,000 | 2,075,000
Retained Earnings |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Stockholders' equity |  | $ (216,593,000) |  | (211,859,000) |  | $ (194,295,000) | (188,877,000)
Cumulative effect adjustment for the adoption of ASC 326 |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Stockholders' equity | [2] |  |  | 1,076,000 |  |  |
Allowance for credit losses |  |  |  | 374,000 |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Unfunded Loan Commitment |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | 1,082,000 |  |  | $ 0
Cumulative effect adjustment for the adoption of ASC 326 | Loan Portfolio |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | 400,000 |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Securities Portfolio |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | 0 |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Commercial Mortgages |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | (695,000) |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Commercial Mortgages | Commercial And Agricultural And Commercial Real Estate |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | 200,000 |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Consumer Loans |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Allowance for credit losses |  |  |  | 176,000 |  |  |
Cumulative effect adjustment for the adoption of ASC 326 | Retained Earnings |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Stockholders' equity, before tax |  |  |  | 1,500,000 |  |  |
Stockholders' equity | [2] |  |  | $ 1,076,000 |  |  |
[1] | Effective January 1, 2023, the allowance calculation is based upon Current Expected Credit loss methodology. Prior to January 1, 2023, the allowance calculation was based upon incurred loss methodology. Refer to Note 1 for further discussion.
[2] | Due to implementation of ASC 326. See "Adoption of New Accounting Standards" discussion in Note 1.

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