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Fair Value of Assets and Liabilities - Carrying Value and Estimated Fair Value of Senior Notes (Details) - USD ($) $ in Thousands | Sep. 29, 2018 | Dec. 30, 2017
--- | --- | ---
Carrying Value | Euro Senior Notes, Series A due 2023 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | $ 136,819 | $ 139,623
Carrying Value | Euro Senior Notes, Series B due 2028 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 111,092 | 113,369
Carrying Value | U.S. Senior Notes, Series A due 2022 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 25,000 | 25,000
Carrying Value | U.S. Senior Notes, Series B due 2027 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 100,000 | 100,000
Carrying Value | U.S. Senior Notes, Series A due 2025 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 50,000 | 0
Carrying Value | U.S. Senior Notes, Series B due 2030 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 125,000 | 0
Estimated Fair Value | Euro Senior Notes, Series A due 2023 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 135,392 | 138,294
Estimated Fair Value | Euro Senior Notes, Series B due 2028 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 108,511 | 111,579
Estimated Fair Value | U.S. Senior Notes, Series A due 2022 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 24,052 | 24,737
Estimated Fair Value | U.S. Senior Notes, Series B due 2027 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 94,474 | 99,992
Estimated Fair Value | U.S. Senior Notes, Series A due 2025 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | 47,333 | 0
Estimated Fair Value | U.S. Senior Notes, Series B due 2030 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt fair value | $ 115,231 | $ 0

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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