Other Comprehensive Earnings (Loss), Changes in the components of accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			$ (239,425)	$ (194,570)
Adoption of ASU 2018-02			(21,503)
Other Comprehensive Earnings (Loss), Net of Tax, Total	$ (1,662)	$ (8,179)	(35,810)	(40,222)
Total accumulated other comprehensive earnings (loss), End of Period	(296,738)	(234,792)	(296,738)	(234,792)
Pension and Postretirement Amounts [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			(110,971)	(118,401)
Adoption of ASU 2018-02			(18,065)
Other Comprehensive Earnings (Loss), Net of Tax, Total			(19,660)	4,345
Total accumulated other comprehensive earnings (loss), End of Period	(148,696)	(114,056)	(148,696)	(114,056)
Gains (Losses) On Derivative Instruments [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			(32,827)	51,085
Adoption of ASU 2018-02			(3,660)
Other Comprehensive Earnings (Loss), Net of Tax, Total			29,083	(85,966)
Total accumulated other comprehensive earnings (loss), End of Period	(7,404)	(34,881)	(7,404)	(34,881)
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	(19,659)		(19,659)
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	12,255		12,255
Unrealized Holding Gains (Losses) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			1,034	1,424
Adoption of ASU 2018-02			222
Other Comprehensive Earnings (Loss), Net of Tax, Total			(673)	(555)
Total accumulated other comprehensive earnings (loss), End of Period	583	869	583	869
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive (Loss) [Line Items]
Total accumulated other comprehensive earnings (loss), Beginning of Year			(96,661)	(128,678)
Adoption of ASU 2018-02			0
Other Comprehensive Earnings (Loss), Net of Tax, Total			(44,560)	41,954
Total accumulated other comprehensive earnings (loss), End of Period	$ (141,221)	$ (86,724)	$ (141,221)	$ (86,724)