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PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Nonunion) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Pension and other postretirement benefit plans |  |  |
Pension settlement expense |  | $ 89 | $ 8,135
Pension settlement expense, net of tax | $ 5,850 | 66 | 7,063
Nonunion Defined Benefit Pension Plan |  |  |
Pension and other postretirement benefit plans |  |  |
Pension settlement expense | 2,530 |  | 4,164
Pension settlement expense, net of tax | 1,900 |  | 3,100
Lump-sum distributions | 16,000 |  | 33,900
Noncash charge to pension settlement expense | 4,000 |  | 4,000
Noncash charge to pension settlement expense, Tax | $ 0 |  | $ 0
Supplemental Benefit Plan |  |  |
Pension and other postretirement benefit plans |  |  |
Benefit |  | 700 |
Pension settlement expense |  | 89 |
Pension settlement expense, net of tax |  | $ 100 |

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=109237824&loc=SL108413299-114919 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 + Details
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