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PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Nonunion) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) person | Jun. 30, 2016 USD ($)
Pension and other postretirement benefit plans |  |  |  |  |
Pension settlement expense, pre-tax | $ 700 |  | $ 600 | $ 2,701 | $ 1,464
Pension settlement expense, net of tax | 454 |  | 345 | $ 1,650 | 895
Nonunion Defined Benefit Pension Plan |  |  |  |  |
Pension and other postretirement benefit plans |  |  |  |  |
Number of plan participants for which vested pension benefits were settled | person |  |  |  | 50 |
Pension settlement expense, pre-tax | 744 |  | 564 | $ 2,701 | 1,464
Pension settlement expense, net of tax | 500 |  | 300 | 1,700 | 900
Lump-sum distributions | $ 4,900 |  | $ 2,700 | $ 9,700 | $ 7,200
Premium paid to purchase nonparticipating annuity contract |  | $ 7,600 |  |  |

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- Definition Amount of premium paid for nonparticipating annuity contract to settle vested benefit obligations of participants and beneficiaries receiving monthly benefits. + References No definition available. + Details
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- Definition Net of tax amount of the gain (loss) adjustment to other comprehensive income (loss) resulting from the settlement of the entity's defined benefit pension and other postretirement plans. + References No definition available. + Details
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- Definition Number of participants and beneficiaries for which vested benefit obligations were settled with nonparticipating annuity contract. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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