EMPLOYEE STOCK PLANS - Net Share-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 01, 2016	Apr. 03, 2015	Apr. 01, 2016	Apr. 03, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 12,550	$ 12,501	$ 23,805	$ 25,238
Income tax benefit for share-based compensation	(3,799)	(3,943)	(7,257)	(7,916)
Cost of revenues - Product
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	1,117	1,206	2,108	2,315
Cost of revenues - Service
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	960	986	1,949	1,938
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	1,746	1,654	3,323	3,392
Selling, general and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 8,727	$ 8,655	$ 16,425	$ 17,593