Other Comprehensive Earnings (Loss), Changes in the components of accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 25, 2016	Sep. 27, 2015	Sep. 25, 2016	Sep. 27, 2015
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			$ (146,001)	$ (95,454)
Other Comprehensive Earnings (Loss), Net of Tax, Total	$ (29,688)	$ (22,709)	(57,988)	(30,731)
Total accumulated other comprehensive earnings (loss), End of Period	(203,989)	(126,185)	(203,989)	(126,185)
Pension and Postretirement Amounts [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			(102,931)	(113,092)
Other Comprehensive Earnings (Loss), Net of Tax, Total			3,523	6,855
Total accumulated other comprehensive earnings (loss), End of Period	(99,408)	(106,237)	(99,408)	(106,237)
Gains (Losses) On Derivative Instruments [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			79,317	43,689
Other Comprehensive Earnings (Loss), Net of Tax, Total			(80,956)	48,459
Total accumulated other comprehensive earnings (loss), End of Period	(1,639)	92,148	(1,639)	92,148
Gains (Losses) On Derivative Instruments [Member] | Interest Rate Contract [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), End of Period	(18,503)		(18,503)
Gains (Losses) On Derivative Instruments [Member] | Foreign Exchange Forward [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), End of Period	16,864		16,864
Unrealized Holding Gains on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			1,258	1,900
Other Comprehensive Earnings (Loss), Net of Tax, Total			963	(290)
Total accumulated other comprehensive earnings (loss), End of Period	2,221	1,610	2,221	1,610
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			(123,645)	(27,951)
Other Comprehensive Earnings (Loss), Net of Tax, Total			18,482	(85,755)
Total accumulated other comprehensive earnings (loss), End of Period	$ (105,163)	$ (113,706)	$ (105,163)	$ (113,706)