Restructuring and Other Charges (Additional Information) (Details) $ in Thousands	3 Months Ended
	Dec. 29, 2018 USD ($) employee	Dec. 30, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net	$ 18,493	$ 105
Free rent and estimated sublease income new headquarters	30,000
estimated undiscounted cash flows old headquarters	29,000
Facility closures and related costs
Restructuring Cost and Reserve [Line Items]
Assumed Sublease Income	1,900
Accrued Expenses and Other Current Liabilities [Member] | Facility closures and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,300	2,200
Other Noncurrent Liabilities [Member] | Facility closures and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,000	$ 2,100
Restructuring Plan 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net	$ 16,300
Restructuring and Related Cost, Number of Positions Eliminated | employee	240
Prior Year Plans [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net	$ 300
Prior Headquarters [Member] | Facility closures and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	24,000
Depreciation	$ 1,900