Other Comprehensive Loss_Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2018	Dec. 31, 2017	Dec. 25, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year	$ (239,425)	$ (194,570)	$ (146,001)
Adoption of ASU 2018-02	(21,503)
Current period other comprehensive earnings (loss)	(45,180)	(57,120)	52
Reclassifications from AOCE to earnings	11,594	12,265	(48,621)
Total accumulated other comprehensive earnings (loss), End of Period	(294,514)	(239,425)	(194,570)
Pension and Postretirement Amounts [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year	(110,971)	(118,401)	(102,931)
Adoption of ASU 2018-02	(18,065)
Current period other comprehensive earnings (loss)	(23,763)	1,555	(20,829)
Reclassifications from AOCE to earnings	9,665	5,875	5,359
Total accumulated other comprehensive earnings (loss), End of Period	(143,134)	(110,971)	(118,401)
Gains (Losses) On Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year	(32,827)	51,085	79,317
Adoption of ASU 2018-02	(3,660)
Current period other comprehensive earnings (loss)	36,107	(90,302)	25,748
Reclassifications from AOCE to earnings	1,929	6,390	(53,980)
Total accumulated other comprehensive earnings (loss), End of Period	1,549	(32,827)	51,085
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year	(96,661)	(128,678)	(123,645)
Adoption of ASU 2018-02	0
Current period other comprehensive earnings (loss)	(55,524)	32,017	(5,033)
Reclassifications from AOCE to earnings	0	0	0
Total accumulated other comprehensive earnings (loss), End of Period	(152,185)	(96,661)	(128,678)
Unrealized Holding Gains on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year	1,034	1,424	1,258
Adoption of ASU 2018-02	222
Current period other comprehensive earnings (loss)	(2,000)	(390)	166
Reclassifications from AOCE to earnings	0	0	0
Total accumulated other comprehensive earnings (loss), End of Period	(744)	$ 1,034	$ 1,424
Interest Rate Contract [Member] \| Gains (Losses) On Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), End of Period	(19,313)
Foreign Exchange Forward [Member] \| Gains (Losses) On Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), End of Period	$ 20,861

Impact to components of accumulated other comprehensive loss due to adoption of ASU 2018-02.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss).

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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