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STOCKHOLDERS' EQUITY (Reclass) (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Unrecognized Net Periodic Benefit Credit (cost) |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax | $ 352 | $ (9,115)
Tax benefit (expense) | (91) | 1,324
Total, net of tax | 261 | (7,791)
Unrecognized Net Periodic Benefit Credit (cost) | Nonunion Defined Benefit Pension Plan |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax |  | (7,300)
Amortization of net actuarial gain (loss) |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax | 441 | (1,005)
Amortization of net actuarial gain (loss) | Nonunion Defined Benefit Pension Plan |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax |  | (300)
Amortization of prior service credit |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax |  | 25
Pension settlement expense, including termination expense |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax | $ (89) | (8,135)
Pension settlement expense, including termination expense | Nonunion Defined Benefit Pension Plan |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax |  | (8,100)
Pension termination expense | Nonunion Defined Benefit Pension Plan |  |
Significant reclassifications out of accumulated other comprehensive loss by component |  |
Total, pre-tax |  | (4,000)
Tax benefit (expense) |  | $ 0

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