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OTHER COMPREHENSIVE INCOME (LOSS) Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
AFS Debt Securities: |  |  |  |
Unrealized holding gains, pre-tax amount | $ 2,925 | $ 9,082 | $ (19,380) | $ 33,197
Unrealized holdings gains, tax (expense) benefit | (629) | (1,952) | 4,167 | (7,137)
Unrealized holdings gains, after-tax amount | 2,296 | 7,130 | (15,213) | 26,060
Net unrealized gains, pre-tax amount | 2,925 | 9,082 | (19,380) | 33,197
Net unrealized gains, tax (expense) benefit | (629) | (1,952) | 4,167 | (7,137)
Net unrealized gains, after-tax amount | 2,296 | 7,130 | (15,213) | 26,060
Cash Flow Hedges: |  |  |  |
Net decrease in fair value, pre-tax amount | (3,203) | 39 | 3,189 | (1,110)
Net decrease in fair value, tax (expense) benefit | 689 | (8) | (685) | 239
Net decrease in fair value, after-tax amount | (2,514) | 31 | 2,504 | (871)
Less: effective portion reclassified into interest expense, after-tax amount | (150) | (21) | (296) | (169)
Net decrease in fair value, pre-tax amount | (3,011) | 66 | 3,567 | (894)
Net decrease in fair value, tax (expense) benefit | 647 | (14) | (767) | 192
Net decrease in fair value, after-tax amount | (2,364) | 52 | 2,800 | (702)
Postretirement Plans: |  |  |  |
Net actuarial gain, after-tax amount | 175 | 137 | 350 | 275
Net gain on postretirement plans, pre-tax amount | 217 | 169 | 435 | 339
Net gain on postretirement plans, tax (expense) benefit | (46) | (36) | (94) | (73)
Net gain on postretirement plans, net of tax | 171 | 133 | 341 | 266
Other comprehensive income, pre-tax amount | 131 | 9,317 | (15,378) | 32,642
Other comprehensive income, tax (expense) benefit | (28) | (2,002) | 3,306 | (7,018)
Other comprehensive income (loss) | 103 | 7,315 | (12,072) | 25,624
Interest Expense, Borrowings |  |  |  |
Cash Flow Hedges: |  |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | (595) | (274) | (1,173) | (515)
Less: effective portion reclassified into interest expense, tax (expense) benefit | 128 | 59 | 252 | 111
Less: effective portion reclassified into interest expense, after-tax amount | (467) | (215) | (921) | (404)
Interest Income, Interest and Fees on Loans |  |  |  |
Cash Flow Hedges: |  |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | 403 | 247 | 795 | 299
Less: effective portion reclassified into interest expense, tax (expense) benefit | (86) | (53) | (170) | (64)
Less: effective portion reclassified into interest expense, after-tax amount | $ 317 | $ 194 | $ 625 | $ 235

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