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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 | 6 Months Ended
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Jun. 30, 2018 | Jul. 01, 2017 | Jun. 30, 2018 | Jul. 01, 2017
Derivative Instrument Detail [Abstract] |  |  |  |
Realized (losses) gains on closed contracts | $ (4,096) | $ 1,868 | $ (2,158) | $ 430
Unrealized (losses) gains on open contracts | (105) | 2,209 | (1,092) | 2,077
Cumulative net pre-tax(losses) gains | $ (4,201) | $ 4,077 | $ (3,250) | $ 2,507

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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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- Definition Aggregate impact of foreign currency derivatives that remain open at the end of the period on earnings for the period. + References No definition available. + Details
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