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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring Narrative (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 USD ($) loan contract borrower | Jun. 30, 2019 contract loan | Jun. 30, 2020 USD ($) loan contract | Jun. 30, 2019 USD ($) loan contract | Dec. 31, 2019 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 12 |  | 12 | 1 |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ | $ 3,641,000 |  | $ 3,641,000 | $ 137,000 |
Financing Receivable, Troubled Debt Restructuring | $ | 9,800,000 |  | 9,800,000 |  | $ 9,000,000.0
Financing Receivable, Troubled Debt Restructuring, Purchased with Credit Deterioration, Increase | $ | 600,000 |  | 600,000 |  | 2,300,000
Financing Receivable, Modifications, Recorded Investment, Still Accruing | $ | 1,400,000 |  | 1,400,000 |  | 900,000
Financing Receivable, Modifications, Recorded Investment, Nonaccrual Status | $ | 8,400,000 |  | 8,400,000 |  | 8,100,000
Additional Amounts Committed to Customers with Loans Classified as Troubled Debt Restructurings | $ | 29,000 |  | 29,000 |  | $ 17,000
Allowance for Loan and Lease Losses, Period Increase (Decrease) | $ | 200,000 |  | $ 200,000 |  |
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down | $ | $ 0 |  |  |  |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | contract | 0 | 0 | 0 | 0 |
Interest Rate Below Market Reduction |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans |  | 0 |  |  |
Financing Receivable, Modifications, Number of Days Past Due | 30 days |  |  |  |
Interest Rate Below Market Reduction | Commercial and industrial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 2 |  |  |  |
Interest Rate Below Market Reduction | Commercial and industrial | Non-accrual Status |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 1 |  |  |  |
Principal Forgiveness |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Financing Receivable, Modifications, Extension Period |  |  |  | 3 years |
Commercial mortgages | Interest Rate Below Market Reduction |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 4 |  |  |  |
Financing Receivable, Modifications, Number of Borrowers | borrower | 3 |  |  |  |
Commercial mortgages | Interest Rate Below Market Reduction | Substandard | Non-accrual Status |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  |  |  |
Commercial mortgages | Interest Rate Below Market Reduction | Substandard | Non-accrual Status | 30 - 59 Days Past Due |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 2 |  |  |  |
Home equity lines and loans | Interest Rate Below Market Reduction |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  |  |  |
Home equity lines and loans | Interest Rate Below Market Reduction | Substandard | Non-accrual Status |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  |  |  |
Residential mortgages | Interest Rate Below Market Reduction |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  |  |  |
Residential mortgages | Interest Rate Below Market Reduction | Non-accrual Status |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  |  |  |
Residential mortgages | Interest Rate Below Market Reduction | Substandard | Non-accrual Status |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 2 |  |  |  |
Residential mortgages | Interest Rate Below Market Reduction | Substandard | Non-accrual Status | 30 - 59 Days Past Due |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 1 |  |  |  |
Commercial And Consumer Portfolio Segment |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans |  |  | 1,168 |  |
Number of Loans Remaining in Modified Status |  |  | 593 |  |
Loan Balance Remaining in Modified Status | $ |  |  | $ 185,800,000 |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ |  |  | $ 241,600,000 |  |
Consumer Loans | Home equity lines and loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans | 3 |  | 3 | 1 |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ | $ 738,000 |  | $ 738,000 | $ 137,000 |
Consumer Loans | Home equity lines and loans | Interest Rate Below Market Reduction |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Number of loans |  |  |  | 1 |

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