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Schedule of Net Periodic Pension and Postretirement (income) Cost (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Defined Benefit Plan Disclosure |  |  |
Net actuarial (gain) loss | $ (6,624) | $ (3,203) | $ 17,732
United States Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Service cost | 2,239 | 2,302 | 2,462
Interest cost | 13,151 | 13,630 | 13,142
Expected return on plan assets | (12,008) | (13,830) | (14,517)
Amortization of prior service cost | 70 | 96 | 134
Net actuarial (gain) loss | (6,712) | (4,013) | 10,596
Total net periodic pension (income) cost | (3,260) | (1,815) | 11,817
Prior service cost | (70) | (96) | (134)
Total recognized in other comprehensive income | (70) | (96) | (134)
Total recognized in net periodic pension (income) cost and other comprehensive income | (3,330) | (1,911) | 11,683
Foreign Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure |  |  |
Service cost | 818 | 761 | 1,006
Interest cost | 852 | 1,185 | 1,444
Expected return on plan assets | (165) | (443) | (781)
Net actuarial (gain) loss | (310) | 815 | 8,415
Curtailment |  |  | (634)
Total net periodic pension (income) cost | 1,195 | 2,318 | 9,450
Total recognized in net periodic pension (income) cost and other comprehensive income | 1,195 | 2,318 | 9,450
Postretirement Benefit Plans |  |  |
Defined Benefit Plan Disclosure |  |  |
Service cost | 34 | 37 | 48
Interest cost | 201 | 218 | 237
Amortization of prior service cost | (496) | (607) | (598)
Net actuarial (gain) loss | 398 | 5 | (648)
Special termination benefits | 591 |  |
Total net periodic pension (income) cost | 728 | (347) | (961)
Prior service cost |  | (93) |
Prior service credit | 496 | 607 | 598
Total recognized in other comprehensive income | 496 | 514 | 598
Total recognized in net periodic pension (income) cost and other comprehensive income | $ 1,224 | $ 167 | $ (363)

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- Definition Amount recognized in net periodic benefit cost (credit) and other comprehensive (income) loss. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921 + Details
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