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EMPLOYEE BENEFIT PLANS (Plans) (Details) $ in Thousands | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 31, 2014 USD ($) person | Dec. 31, 2016 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2015 USD ($)
Nonunion Defined Benefit Pension Plan |  |  |  |
Nonunion Defined Benefit Pension, Supplemental Benefit, and Postretirement Health Benefit Plans |  |  |  |
Number of plan participants for which vested pension benefits were settled | person | 375 |  |  |
Premium paid to purchase nonparticipating annuity contract | $ 25,400 |  | $ 25,400 |
Pension benefit obligation settled with nonparticipating annuity contract | $ 23,300 |  |  |
Lump-sum distributions |  |  | $ 32,100 |
Unrecognized net actuarial loss |  | $ 23,294 |  | $ 28,457
Amortization period for unrecognized net actuarial loss |  | 8 years |  |
Postretirement Health Benefit Plan |  |  |  |
Nonunion Defined Benefit Pension, Supplemental Benefit, and Postretirement Health Benefit Plans |  |  |  |
Unrecognized net actuarial loss |  | $ 5,708 |  | $ 6,280
Unrecognized prior service credit, amortization period |  | 9 years |  |

X
- Definition The average remaining future years of service of plan participants over which the unrecognized net actuarial loss will be amortized. + References No definition available. + Details
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X
- Definition Amount of defined benefit plan benefit obligation related to vested benefit obligations of participants and beneficiaries receiving monthly benefits which was settled with nonparticipating annuity contract. + References No definition available. + Details
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X
- Definition The amount of lump sum benefit distributions paid. + References No definition available. + Details
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X
- Definition The period over which the unrecognized prior service cost (credit) is being amortized. + References No definition available. + Details
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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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X
- 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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X
- Definition The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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X
- 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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- Details
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