Employee Benefit Plans and Non-Qualified Plans - Weighted Average Assumptions Used in Determining the Benefit Obligations (Detail)	Dec. 31, 2017	Dec. 31, 2016
Non-U.S. Qualified Defined Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.50%	3.75%
Non Qualified Supplemental Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.35%	3.55%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant