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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Narrative (Details) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) contract | Jun. 30, 2020 USD ($) contract | Dec. 31, 2020 USD ($) contract
Financing Receivable Allowance For Credit Losses [Line Items] |  |  |  |  |
Allowance for credit losses provision | $ (1,000,000) | $ 12,100,000 | $ (1,000,000) | $ 13,500,000 |
Loan basis points |  |  | 14.00% |  |
Loans classified in doubtful or loss risk rating | 0 |  | $ 0 |  |
Number of loans modified as TDRs | contract |  |  | 1 | 0 | 4
Increase in allowance for loan losses due to TDRs |  |  | $ 0 |  | $ 0
Troubled debt restructuring charge-offs |  |  | $ 0 |  | 0
Provision for Other Credit Losses | $ 1,000,000.0 |  |  |  |
COVID-19 |  |  |  |  |
Financing Receivable Allowance For Credit Losses [Line Items] |  |  |  |  |
Allowance for credit losses provision |  |  |  |  | $ 13,200,000

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