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Note 7 - Fair Value of Assets and Liabilities - Carrying Value and Estimated Fair Value of Senior Notes (Details) - USD ($) $ in Thousands | Dec. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Euro Senior Notes, Series A [Member] | Reported Value Measurement [Member] |  |
Senior Notes, Fair Value | $ 139,623 | $ 122,313
Euro Senior Notes, Series A [Member] | Estimate of Fair Value Measurement [Member] |  |
Senior Notes, Fair Value | 138,294 | 122,586
Euro Senior Notes, Series B [Member] | Reported Value Measurement [Member] |  |
Senior Notes, Fair Value | 113,369 | 95,314
Euro Senior Notes, Series B [Member] | Estimate of Fair Value Measurement [Member] |  |
Senior Notes, Fair Value | 111,579 | 99,230
US Senior Notes A Due 2022 [Member] | Reported Value Measurement [Member] |  |
Senior Notes, Fair Value | 25,000 | 25,000
US Senior Notes A Due 2022 [Member] | Estimate of Fair Value Measurement [Member] |  |
Senior Notes, Fair Value | 24,737 | 24,746
US Senior Notes B Due 2027 [Member] | Reported Value Measurement [Member] |  |
Senior Notes, Fair Value | 100,000 | 100,000
US Senior Notes B Due 2027 [Member] | Estimate of Fair Value Measurement [Member] |  |
Senior Notes, Fair Value | $ 99,992 | $ 98,660

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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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