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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Narrative (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) Contract | Dec. 31, 2020 USD ($) Contract | Dec. 31, 2019 USD ($) Contract
Financing Receivable Allowance For Credit Losses [Line Items] |  |  |  |  |  |
Loans to related parties |  |  |  | $ 44,052,000 | $ 52,559,000 |
Allowance for credit losses provision |  |  |  | (1,700,000) | 13,200,000 | $ 1,250,000
Loans classified in doubtful or loss risk rating |  |  |  | $ 0 | $ 0 |
Number of loans modified as TDRs | Contract |  |  |  | 1 | 4 | 4
Increase in allowance for loan losses due to TDRs |  |  |  | $ 0 | $ 0 |
Troubled debt restructuring charge-offs |  |  |  | 0 | 0 |
Interest income if accrual method |  |  |  | 141,000 | 821,000 |
Unfunded commitments of related party loans |  |  |  | $ 40,244,000 |  |
COVID-19 |  |  |  |  |  |
Financing Receivable Allowance For Credit Losses [Line Items] |  |  |  |  |  |
Allowance for credit losses provision |  |  |  |  | $ 13,200,000 |
Provision for Other Credit Losses | $ 700,000 | $ 1,000,000 | $ 0 |  |  |

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554 + Details
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