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OTHER COMPREHENSIVE INCOME (LOSS) Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Jun. 30, 2022 | Dec. 31, 2021 | Jun. 30, 2021 | Dec. 31, 2020
AFS Debt Securities: |  |  |  |  |  |  |  |
Unrealized holding gains, pre-tax amount | $ (28,432) | $ (6,546) | $ (173,421) | $ (25,926) |  |  |  |
Unrealized holdings gains, tax (expense) benefit | 6,113 | 1,407 | 37,286 | 5,574 |  |  |  |
Unrealized holdings gains, after-tax amount | (22,319) | (5,139) | (136,135) | (20,352) |  |  |  |
Less: reclassification adjustment for amortization of securities transferred from AFS to HTM, pre-tax amount | 2,436 | 0 | 3,780 | 0 |  |  |  |
Less: reclassification adjustment for amortization of securities transferred from AFS to HTM, tax (expense) benefit | (524) | 0 | (813) | 0 |  |  |  |
Less: reclassification adjustment for amortization of securities transferred from AFS to HTM, after-tax amount | 1,912 | 0 | 2,967 | 0 |  |  |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  |  | (9) | 0 |  |  |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax |  |  | 2 | 0 |  |  |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax |  |  | (7) | 0 |  |  |  |
Net unrealized gains, pre-tax amount | (30,868) | (6,546) | (177,192) | (25,926) |  |  |  |
Net unrealized gains, tax (expense) benefit | 6,637 | 1,407 | 38,097 | 5,574 |  |  |  |
Net unrealized gains, after-tax amount | (24,231) | (5,139) | (139,095) | (20,352) |  |  |  |
Cash Flow Hedges: |  |  |  |  |  |  |  |
Net decrease in fair value, pre-tax amount | 3,381 | 466 | 10,604 | 3,655 |  |  |  |
Net decrease in fair value, tax (expense) benefit | (727) | (100) | (2,280) | (785) |  |  |  |
Net decrease in fair value, after-tax amount | 2,654 | 366 | 8,324 | 2,870 |  |  |  |
Net decrease in fair value, pre-tax amount | 3,261 | 595 | 10,604 | 4,162 |  |  |  |
Net decrease in fair value, tax (expense) benefit | (701) | (128) | (2,280) | (895) |  |  |  |
Net decrease in fair value, after-tax amount | 2,560 | 467 | 8,324 | 3,267 |  |  |  |
Postretirement Plans: |  |  |  |  |  |  |  |
Net gain on postretirement plans, pre-tax amount | 230 | 217 | 693 | 652 |  |  |  |
Net gain on postretirement plans, tax (expense) benefit | (49) | (46) | (149) | (140) |  |  |  |
Net gain on postretirement plans, net of tax | 181 | 171 | 544 | 512 |  |  |  |
Other comprehensive income, pre-tax amount | (27,377) | (5,734) | (165,895) | (21,112) |  |  |  |
Other comprehensive income, tax (expense) benefit | 5,887 | 1,233 | 35,668 | 4,539 |  |  |  |
Other comprehensive loss | (21,490) | (4,501) | (130,227) | (16,573) |  |  |  |
Allowance for credit losses | 36,542 | 32,272 | 36,542 | 32,272 | $ 34,244 | $ 33,256 | $ 32,060 | $ 37,865
Commercial real estate - non-owner-occupied, hospitality-related |  |  |  |  |  |  |  |
Postretirement Plans: |  |  |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  | $ 5,000 |  |
Interest Expense, Borrowings |  |  |  |  |  |  |  |
Cash Flow Hedges: |  |  |  |  |  |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | 241 | (539) | (498) | (1,712) |  |  |  |
Less: effective portion reclassified into interest expense, tax (expense) benefit | (52) | 116 | 107 | 368 |  |  |  |
Less: effective portion reclassified into interest expense, after-tax amount | 189 | (423) | (391) | (1,344) |  |  |  |
Interest Income, Interest and Fees on Loans |  |  |  |  |  |  |  |
Cash Flow Hedges: |  |  |  |  |  |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | (121) | 410 | 498 | 1,205 |  |  |  |
Less: effective portion reclassified into interest expense, tax (expense) benefit | 26 | (88) | (107) | (258) |  |  |  |
Less: effective portion reclassified into interest expense, after-tax amount | $ (95) | $ 322 | $ 391 | $ 947 |  |  |  |

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