Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 27, 2020	Mar. 29, 2019	Mar. 27, 2020	Mar. 29, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			$ 5,714,691
Other comprehensive income (loss)	$ (66,151)	$ (3,708)	(29,505)	$ (53,557)
Ending balance	5,561,783		5,561,783
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(916,812)
Other comprehensive income (loss)			(37,358)
Reclassifications from other comprehensive income (loss)			7,853
Ending balance	(946,317)		(946,317)
Change in Pension Liabilities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(436,749)
Other comprehensive income (loss)			8,473
Reclassifications from other comprehensive income (loss)			7,853
Ending balance	(420,423)		(420,423)
Foreign Currency Translation Adjustment
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(480,045)
Other comprehensive income (loss)			(45,849)
Reclassifications from other comprehensive income (loss)			0
Ending balance	(525,894)		(525,894)
Gain/(Loss) on Cash Flow Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(18)
Other comprehensive income (loss)			18
Reclassifications from other comprehensive income (loss)			0
Ending balance	$ 0		$ 0