Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by Component) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss)	$ 5,704	$ 24,400	$ 1,800	$ 40,254
Accumulated foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCIL beginning of period			(99,415)
Other comprehensive income (loss) before reclassifications			(4,650)
Amounts reclassified from AOCIL			(3,631)
Other comprehensive income (loss)			(8,281)
AOCIL end of period	(107,696)		(107,696)
Accumulated retirement liability
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCIL beginning of period			(272,317)
Other comprehensive income (loss) before reclassifications			687
Amounts reclassified from AOCIL			8,809
Other comprehensive income (loss)			9,496
AOCIL end of period	(262,821)		(262,821)
Accumulated gain (loss) on derivatives
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCIL beginning of period			(449)
Other comprehensive income (loss) before reclassifications			529
Amounts reclassified from AOCIL			56
Other comprehensive income (loss)			585
AOCIL end of period	136		136
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCIL beginning of period			(372,181)
Other comprehensive income (loss) before reclassifications			(3,434)
Amounts reclassified from AOCIL			5,234
Other comprehensive income (loss)	5,704	$ 24,400	1,800	$ 40,254
AOCIL end of period	$ (370,381)		$ (370,381)