Income Taxes (Components of Net Deferred Tax Assets) (Details) - USD ($) $ in Thousands	Sep. 29, 2017	Sep. 30, 2016
Obligations relating to:
Defined benefit pension plans	$ 52,299	$ 77,834
Other employee benefit plans	192,299	179,063
Net Operating Losses	136,783	139,125
Self-insurance programs	489	1,722
Contract revenues and costs	(18,374)	(8,177)
Deferred Rent	25,654	7,955
Restructuring	18,258	47,792
Other	19,389	9,933
Valuation Allowance	(58,097)	(41,684)
Gross deferred tax assets	368,700	413,563
Deferred tax liabilities:
Depreciation and amortization	(176,327)	(154,939)
Other, net	(1,438)	(1,555)
Gross deferred tax liabilities	(177,765)	(156,494)
Net deferred tax assets	$ 190,935	$ 257,069