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PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Nonunion) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) person | Sep. 30, 2016 USD ($) | Jun. 30, 2017 | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($)
Pension and other postretirement benefit plans |  |  |  |  |  |
Pension settlement expense, pre-tax |  |  |  |  | $ 3,644 | $ 2,267
Pension settlement expense, net of tax | $ 577 |  | $ 490 |  | 2,227 | 1,385
Nonunion Defined Benefit Pension Plan |  |  |  |  |  |
Pension and other postretirement benefit plans |  |  |  |  |  |
Expected return on plan assets (as a percent) | 2.50% |  |  | 6.50% |  |
Number of plan participants for which vested pension benefits were settled | person |  | 50 |  |  |  |
Pension settlement expense, pre-tax | $ 943 |  | 803 |  | 3,644 | 2,267
Pension settlement expense, net of tax | 600 |  | 500 |  | 2,200 | 1,400
Lump-sum distributions | $ 5,800 |  | $ 4,300 |  | $ 15,500 | $ 11,600
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 Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + 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 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/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=82843861&loc=d3e1928-114920 + Details
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- Details
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