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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Allowance for credit loss - loans |  |  |
Beginning balance | $ 66,669 |  |
Charge-offs |  |  | $ (784)
Ending balance | 70,091 |  | 66,669
Accrued interest receivable on loans | 34,400 |  |
Amount pledged | 9,813,409 |  | 9,637,929
Amounts outstanding | 394,400 |  |
Foreclosures in progress | 5,200 |  | 5,800
Sale of secondary market eligible residential consumer mortgage loans | 1,200 |  |
Provision | 6,148 | $ 3,500 |
Liabilities for off-balance-sheet |  |  |
Beginning balance | 913 | 1,123 | 1,123
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Provision | (115) | (122) |
Ending balance | 798 | 1,001 | 913
Assets pledged as collateral | Borrowings from FHLB and FRB |  |  |
Allowance for credit loss - loans |  |  |
Amount pledged | 4,440,000 |  |
Elmira Savings Bank ("Elmira") |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 66,700 |  |
Ending balance | 70,100 | 63,200 | 66,700
Commercial Loan |  |  |
Allowance for credit loss - loans |  |  |
Charge-offs | (261) |  |
Consumer indirect |  |  |
Allowance for credit loss - loans |  |  |
Charge-offs | (3,060) |  | (9,352)
Consumer direct |  |  |
Allowance for credit loss - loans |  |  |
Charge-offs | (873) |  | (2,009)
Home equity |  |  |
Allowance for credit loss - loans |  |  |
Charge-offs | (23) |  | (119)
Consumer mortgage |  |  |
Allowance for credit loss - loans |  |  |
Charge-offs | (93) |  | (669)
Commercial Portfolio Segment | Commercial Loan |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 26,854 | 23,297 | 23,297
Charge-offs | (261) | (175) |
Recoveries | 39 | 172 |
Provision | 2,739 | 1,933 |
Ending balance | 29,371 | 25,227 | 26,854
Residential Portfolio Segment | Home equity |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 1,628 | 1,594 | 1,594
Charge-offs | (23) | 0 |
Recoveries | 3 | 6 |
Provision | (27) | (12) |
Ending balance | 1,581 | 1,588 | 1,628
Residential Portfolio Segment | Consumer mortgage |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 15,333 | 14,343 | 14,343
Charge-offs | (93) | (19) |
Recoveries | 3 | 7 |
Provision | (753) | (53) |
Ending balance | 14,490 | 14,278 | 15,333
Consumer Portfolio Segment | Consumer indirect |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 18,585 | 17,852 | 17,852
Charge-offs | (3,060) | (2,531) |
Recoveries | 1,209 | 1,347 |
Provision | 3,560 | 1,379 |
Ending balance | 20,294 | 18,047 | 18,585
Consumer Portfolio Segment | Consumer direct |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 3,269 | 2,973 | 2,973
Charge-offs | (873) | (505) |
Recoveries | 215 | 187 |
Provision | 744 | 375 |
Ending balance | 3,355 | 3,030 | 3,269
Unallocated |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 1,000 | 1,000 | 1,000
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Provision | 0 | 0 |
Ending balance | 1,000 | 1,000 | 1,000
Allowances For Credit Losses [Member] |  |  |
Allowance for credit loss - loans |  |  |
Beginning balance | 66,669 | 61,059 | 61,059
Charge-offs | (4,310) | (3,230) |
Recoveries | 1,469 | 1,719 |
Provision | 6,263 | 3,622 |
Ending balance | 70,091 | 63,170 | 66,669
Total Allowances For Credit Losses [Member] |  |  |
Allowance for credit loss |  |  |
Beginning balance | 67,582 | 62,182 | 62,182
Charge-offs | (4,310) | (3,230) |
Recoveries | 1,469 | 1,719 |
Provision | 6,148 | 3,500 |
Ending balance | $ 70,889 | $ 64,171 | $ 67,582

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