Restructuring Charges (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended		20 Months Ended
	Jul. 01, 2017 USD ($)	Jul. 02, 2016 USD ($)	Jul. 01, 2017 USD ($) employee	Jul. 02, 2016 USD ($)	Jul. 01, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Restructuring Cost and Reserve [Line Items]
Charge to operations, net	$ 1,551	$ 2,815	$ 8,300	$ 44,541	$ 85,500
Restructuring Reserve	8,172	9,994	8,172	9,994	8,172	$ 36,608	$ 15,254
Employee severance and related benefits [Member]
Restructuring Cost and Reserve [Line Items]
Charge to operations, net			2,582	44,010
Restructuring Reserve	2,980	9,140	2,980	9,140	2,980	35,177	14,086
Facility closures and related costs [Member]
Restructuring Cost and Reserve [Line Items]
Charge to operations, net	1,800		5,718	531
Restructuring Reserve	5,192	$ 854	5,192	$ 854	5,192	$ 1,431	$ 1,168
Restructuring Credit [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs			$ 200
Restructuring Plan 2016 [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated | employee			800
Q116 plan [Domain]
Restructuring Cost and Reserve [Line Items]
Charge to operations, net	1,600		$ 8,300
Accrued Expenses and Other Current Liabilities [Member] | Facility closures and related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	3,000		3,000		3,000
Other Noncurrent Liabilities [Member] | Facility closures and related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	2,200		2,200		2,200
Restructuring Charges [Member] | Facility closures and related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 4,400		$ 4,400		$ 4,400