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OTHER COMPREHENSIVE INCOME (LOSS) Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
AFS Securities: |  |
Unrealized holding gains, pre-tax amount | $ 24,115 | $ 13,884
Unrealized holdings gains, tax (expense) benefit | (5,185) | (2,985)
Unrealized holdings gains, after-tax amount | 18,930 | 10,899
Net unrealized gains, pre-tax amount | 24,115 | 13,884
Net unrealized gains, tax (expense) benefit | (5,185) | (2,985)
Net unrealized gains, after-tax amount | 18,930 | 10,899
Cash Flow Hedges: |  |
Net decrease in fair value, pre-tax amount | (1,149) | (1,178)
Net decrease in fair value, tax (expense) benefit | 247 | 253
Net decrease in fair value, after-tax amount | (902) | (925)
Less: effective portion reclassified into interest expense, pre-tax amount |  | (119)
Less: effective portion reclassified into interest expense, tax (expense) benefit |  | 25
Less: effective portion reclassified into interest expense, after-tax amount | (148) | (94)
Net decrease in fair value, pre-tax amount | (961) | (1,059)
Net decrease in fair value, tax (expense) benefit | 207 | 228
Net decrease in fair value, after-tax amount | (754) | (831)
Postretirement Plans: |  |
Net actuarial gain, pre-tax amount | 175 | 67
Net actuarial gain, tax (expense) benefit | (37) | (14)
Net actuarial gain, after-tax amount | 138 | 53
Less: Amortiaztion of net prior service credits, pre-tax amount | 6 | 6
Less: Amortiaztion of net prior service credits, tax (expense) benefit | (1) | (1)
Less: Amortiaztion of net prior service credits, after-tax amount | 5 | 5
Net gain on postretirement plans, pre-tax amount | 169 | 61
Net gain on postretirement plans, tax (expense) benefit | (36) | (13)
Net gain on postretirement plans, net of tax | 133 | 48
Other comprehensive income, pre-tax amount | 23,323 | 12,886
Other comprehensive income, tax (expense) benefit | (5,014) | (2,770)
Other comprehensive income | 18,309 | $ 10,116
Interest Expense, Borrowings |  |
Cash Flow Hedges: |  |
Less: effective portion reclassified into interest expense, pre-tax amount | (240) |
Less: effective portion reclassified into interest expense, tax (expense) benefit | 52 |
Less: effective portion reclassified into interest expense, after-tax amount | (188) |
Interest Income, Interest and Fees on Loans |  |
Cash Flow Hedges: |  |
Less: effective portion reclassified into interest expense, pre-tax amount | 52 |
Less: effective portion reclassified into interest expense, tax (expense) benefit | (12) |
Less: effective portion reclassified into interest expense, after-tax amount | $ 40 |

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