Stock-Based Compensation - Stock Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 04, 2020	Jun. 29, 2019	Jul. 04, 2020	Jun. 29, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	$ 12,834	$ 8,243	$ 27,662	$ 22,429
Capitalized share-based compensation costs	2,100	1,200	4,300	3,600
Amortization of capitalized share-based compensation expenses	1,200	1,200	3,400	3,600
Total compensation cost, unvested stock-based awards granted but not yet recognized	49,500		$ 49,500
Total compensation cost, weighted-average period of amortization (in years)			1 year 4 months 24 days
Share-based Payment Arrangement, Accelerated Cost	3,500
Period End
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Capitalized share-based compensation remaining	2,400	1,500	$ 2,400	1,500
Cost of sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	1,237	1,231	3,430	3,640
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	1,469	794	2,924	2,227
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	11,680	7,630	24,722	20,668
Income tax benefit
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Income tax benefit	$ (1,552)	$ (1,412)	$ (3,414)	$ (4,106)