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PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Tables) | 3 Months Ended
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Mar. 31, 2014
PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS |
Summary of the components of net periodic benefit cost |
|  | Three Months Ended March 31 |
|  | Nonunion Defined |  | Supplemental |  | Postretirement |
|  | Benefit Pension Plan |  | Benefit Plan |  | Health Benefit Plan |
|  | 2014 |  | 2013 |  | 2014 |  | 2013 |  | 2014 |  | 2013 |
|  | (in thousands) |
Service cost |  | $ | — |  | $ | 2,367 |  | $ | — |  | $ | — |  | $ | 70 |  | $ | 83 |
Interest cost |  | 1,720 |  | 1,923 |  | 49 |  | 37 |  | 197 |  | 188 |
Expected return on plan assets |  | (2,831 | ) | (3,154 | ) | — |  | — |  | — |  | — |
Amortization of prior service credit |  | — |  | — |  | — |  | — |  | (47 | ) | (48 | )
Pension settlement expense |  | 3,691 |  | — |  | — |  | — |  | — |  | — |
Amortization of net actuarial loss |  | 498 |  | 2,713 |  | 56 |  | 65 |  | 23 |  | 134 |
Net periodic benefit cost |  | $ | 3,078 |  | $ | 3,849 |  | $ | 105 |  | $ | 102 |  | $ | 243 |  | $ | 357 |
Schedule of changes in the PBO and plan assets of the nonunion defined benefit pension plan |
|  | Nonunion Defined |
|  | Benefit Pension Plan |
|  | (in thousands) |
Change in projected benefit obligation |  |  |
Projected benefit obligation at December 31, 2013 |  | $ | 211,660 |
Interest cost |  | 1,720 |
Actuarial loss (1) |  | 8,329 |
Benefits paid(2) |  | (39,878 | )
Projected benefit obligation at March 31, 2014 |  | 181,831 |
Change in plan assets |  |  |
Fair value of plan assets at December 31, 2013 |  | 207,613 |
Actual return on plan assets |  | 2,492 |
Benefits paid(2) |  | (39,878 | )
Fair value of plan assets at March 31, 2014 |  | 170,227 |
Funded status at March 31, 2014(3) |  | $ | (11,604 | )
Accumulated benefit obligation |  | $ | 181,831 |
(1) Net actuarial loss from remeasurement upon settlements was primarily impacted by changes in the discount rate since the previous remeasurement date. The discount rate used to remeasure the PBO upon settlement was 3.5% compared to a rate of 3.8% as of the December 31, 2013 measurement date. (2) Includes purchase of nonparticipating annuity contract, lump-sum distributions, and periodic payments made by the plan during the three months ended March 31, 2014. (3) Noncurrent liability recognized within pension and postretirement liabilities in the accompanying consolidated balance sheet at March 31, 2014.

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- Definition Tabular disclosure of net funded status of pension plans and/or other employee benefit plans and disclosure of accumulated benefit obligation. + References No definition available. + Details
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + 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) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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