Employee Stock Award and Benefit Plans - Stock Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	$ 15,261	$ 13,985	$ 13,654
Total stock-based compensation cost capitalized as part of inventory	2,700	2,500
Total stock-based compensation cost amortized into income	2,600	2,500
Total compensation cost, unvested stock-based awards granted but not yet recognized	21,200
Nonvested awards, total compensation cost not yet recognized, forfeitures	$ 800
Total compensation cost, weighted-average period of amortization (in years and months)	1 year 4 months 24 days
Total compensation cost not yet recognized, period for recognition	1 month
Cost of sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	$ 2,558	2,530	2,393
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	2,268	1,946	2,033
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	15,331	13,756	14,471
Income tax benefit
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation expense	(4,896)	$ (4,247)	$ (5,243)
Employee Stock Purchase Plans
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total compensation cost, unvested stock-based awards granted but not yet recognized	$ 200