EMPLOYEE STOCK PLANS - Share-based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Sep. 27, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated share-based compensation expense	$ 13.9	$ 13.4	$ 11.7
Cost of revenues
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated share-based compensation expense	1.4	1.1	1.2
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated share-based compensation expense	3.0	2.5	2.2
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated share-based compensation expense	$ 9.5	$ 9.8	$ 8.3