Postretirement Benefits Other Than Pensions - Estimated Benefit Payments for Domestic and Foreign Pension Plans (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	$ 2,779
2019	2,937
2020	3,015
2021	3,095
2022	3,151
2023-2027	16,227
Domestic Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	2,135
2019	2,220
2020	2,249
2021	2,279
2022	2,304
2023-2027	11,352
Foreign Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	644
2019	717
2020	766
2021	816
2022	847
2023-2027	$ 4,875

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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- Definition

Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

+ References

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

+ References

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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