SHAREHOLDERS' EQUITY AND EMPLOYEE BENEFIT PLANS (Total equity-based compensation expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	$ 3,609	$ 3,873
Relative TSR PSU [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	406	1,375
Time-based RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	2,415	2,141
Special/Growth PSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	566	162
Common Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	222	195
Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	232	150
Selling, general and administrative (1) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	2,735	2,925
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total equity-based compensation expense	$ 642	$ 798