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Basis of Presentation and Summary of Significant Accounting Policies - Gains (Losses) on Foreign Exchange Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Derivative Instrument Detail [Abstract]
Realized gains (losses) on closed contracts	$ 1,937	$ (1,438)
Unrealized losses on open contracts	(985)	(132)
Cumulative net pre-tax gains (losses)	$ 952	$ (1,570)

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Aggregate impact of foreign currency derivatives on earnings for the period. Includes impact of foreign currency cash flow hedge ineffectiveness and the ineffectiveness of fair value hedging derivatives and full change in fair value of the foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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Aggregate impact of foreign currency derivatives closed during the period on earnings for the period.

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Aggregate impact of foreign currency derivatives that remain open at the end of the period on earnings for the period.

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