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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) loan | Jun. 30, 2020 USD ($) borrower | Jun. 30, 2021 USD ($) loan | Jun. 30, 2020 USD ($) borrower
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | 2 | 12 | 4 | 12
Pre-Modification Outstanding Recorded Investment | $ 3,606 | $ 3,641 | $ 6,094 | $ 3,641
Post-Modification Outstanding Recorded Investment | $ 3,606 | $ 3,641 | $ 6,094 | $ 3,641
Commercial and industrial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | borrower |  | 2 |  | 2
Pre-Modification Outstanding Recorded Investment |  | $ 929 |  | $ 929
Post-Modification Outstanding Recorded Investment |  | $ 929 |  | $ 929
Commercial loan portfolio | Commercial mortgages |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | 2 | 4 | 4 | 4
Pre-Modification Outstanding Recorded Investment | $ 3,606 | $ 1,297 | $ 6,094 | $ 1,297
Post-Modification Outstanding Recorded Investment | $ 3,606 | $ 1,297 | $ 6,094 | $ 1,297
Residential mortgages |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | borrower |  | 3 |  | 3
Pre-Modification Outstanding Recorded Investment |  | $ 677 |  | $ 677
Post-Modification Outstanding Recorded Investment |  | $ 677 |  | $ 677
Consumer loans: | Home equity lines and loans |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | borrower |  | 3 |  | 3
Pre-Modification Outstanding Recorded Investment |  | $ 738 |  | $ 738
Post-Modification Outstanding Recorded Investment |  | $ 738 |  | $ 738

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