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LOANS - Allowance for Credit Losses (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | $ 60,869 | $ 49,911 | $ 49,911
Charge-offs | (1,966) |  |
Recoveries | 1,585 |  |
Provision | (5,419) |  |
Balance, end of period | 55,069 |  | 60,869
Liabilities for off-balance-sheet credit exposures [Roll Forward] |  |  |
Beginning balance | 1,489 | 0 | 0
Charge-offs | 0 |  |
Recoveries | 0 |  |
Provision | (300) |  |
Ending balance | 1,189 |  | 1,489
Total allowance for credit losses [Roll Forward] |  |  |
Beginning balance | 62,358 | 49,911 | 49,911
Charge-offs | (1,966) |  |
Recoveries | 1,585 |  |
Provision | (5,719) |  |
Ending balance | $ 56,258 |  | $ 62,358
Allowance for Credit Losses |  |  |
Allowance for credit losses to total loans ratio | 0.75 |  |
Basis points lower level | 0.06 |  | 0.07
Accrued interest and fees receivable | $ 20,900 |  |
Minimum [Member] | COVID-19 [Member] |  |  |
Allowance for Credit Losses |  |  |
Percentage of peak unemployment | 3.00% |  |
Maximum [Member] | COVID-19 [Member] |  |  |
Allowance for Credit Losses |  |  |
Percentage of peak unemployment | 8.00% |  |
ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 51,268 | $ 51,268
Charge-offs |  | (3,047) |
Recoveries |  | 1,497 |
Provision |  | 5,934 |
Balance, end of period |  | 55,652 |
Liabilities for off-balance-sheet credit exposures [Roll Forward] |  |  |
Beginning balance |  | 1,185 | 1,185
Charge-offs |  | 0 |
Recoveries |  | 0 |
Provision |  | (340) |
Ending balance |  | 845 |
Total allowance for credit losses [Roll Forward] |  |  |
Beginning balance |  | 52,453 | 52,453
Charge-offs |  | (3,047) |
Recoveries |  | 1,497 |
Provision |  | 5,594 |
Ending balance |  | 56,497 |
ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 1,357 | 1,357
Liabilities for off-balance-sheet credit exposures [Roll Forward] |  |  |
Beginning balance |  | 1,185 | 1,185
Total allowance for credit losses [Roll Forward] |  |  |
Beginning balance |  | 2,542 | 2,542
Acquired Impaired Loans [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 163 | 163
Acquired Impaired Loans [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 0 | 0
Charge-offs |  | 0 |
Recoveries |  | 0 |
Provision |  | 0 |
Balance, end of period |  | 0 |
Acquired Impaired Loans [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | (163) | (163)
Acquired Deteriorated |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | $ 1,882 | 0 | 0
Charge-offs | 0 |  |
Recoveries | 27 |  |
Provision | 87 |  |
Balance, end of period | 1,996 |  | 1,882
Acquired Deteriorated | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 3,072 | 3,072
Charge-offs |  | 0 |
Recoveries |  | 0 |
Provision |  | (26) |
Balance, end of period |  | 3,046 |
Acquired Deteriorated | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 3,072 | 3,072
Commercial Portfolio Segment [Member] | Business Lending [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 28,190 | 19,426 | 19,426
Charge-offs | (51) |  |
Recoveries | 67 |  |
Provision | (1,164) |  |
Balance, end of period | 27,042 |  | 28,190
Commercial Portfolio Segment [Member] | Business Lending [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 19,714 | 19,714
Charge-offs |  | (176) |
Recoveries |  | 138 |
Provision |  | (187) |
Balance, end of period |  | 19,489 |
Commercial Portfolio Segment [Member] | Business Lending [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 288 | 288
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 10,672 | 10,269 | 10,269
Charge-offs | (100) |  |
Recoveries | 10 |  |
Provision | (896) |  |
Balance, end of period | 9,686 |  | 10,672
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 9,218 | 9,218
Charge-offs |  | (186) |
Recoveries |  | 8 |
Provision |  | 3,390 |
Balance, end of period |  | 12,430 |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | (1,051) | (1,051)
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 13,696 | 13,712 | 13,712
Charge-offs | (1,399) |  |
Recoveries | 1,246 |  |
Provision | (2,423) |  |
Balance, end of period | 11,120 |  | 13,696
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 12,715 | 12,715
Charge-offs |  | (2,079) |
Recoveries |  | 1,163 |
Provision |  | 1,895 |
Balance, end of period |  | 13,694 |
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | (997) | (997)
Consumer Portfolio Segment [Member] | Consumer Direct [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 3,207 | 3,255 | 3,255
Charge-offs | (318) |  |
Recoveries | 231 |  |
Provision | (438) |  |
Balance, end of period | 2,682 |  | 3,207
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 2,612 | 2,612
Charge-offs |  | (533) |
Recoveries |  | 182 |
Provision |  | 1,476 |
Balance, end of period |  | 3,737 |
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | (643) | (643)
Consumer Portfolio Segment [Member] | Home Equity [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 2,222 | 2,129 | 2,129
Charge-offs | (98) |  |
Recoveries | 4 |  |
Provision | (585) |  |
Balance, end of period | 1,543 |  | 2,222
Consumer Portfolio Segment [Member] | Home Equity [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 2,937 | 2,937
Charge-offs |  | (73) |
Recoveries |  | 6 |
Provision |  | (386) |
Balance, end of period |  | 2,484 |
Consumer Portfolio Segment [Member] | Home Equity [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 808 | 808
Unallocated Financing Receivables [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period | 1,000 | 957 | 957
Charge-offs | 0 |  |
Recoveries | 0 |  |
Provision | 0 |  |
Balance, end of period | $ 1,000 |  | 1,000
Unallocated Financing Receivables [Member] | ASU 2016-13 [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | 1,000 | 1,000
Charge-offs |  | 0 |
Recoveries |  | 0 |
Provision |  | (228) |
Balance, end of period |  | 772 |
Unallocated Financing Receivables [Member] | ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Balance, beginning of period |  | $ 43 | $ 43

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