SHAREHOLDERS' EQUITY AND EMPLOYEE BENEFIT PLANS (Total equity-based compensation expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	$ 3,873	$ 3,109
Relative TSR PSU [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	1,375	723
Time-based RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	2,141	2,135
Special/Growth PSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	162	56
Common Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	195	195
Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	150	132
Selling, general and administrative (1) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	2,925	2,323
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	$ 798	$ 654