PENSION AND OTHER POSTRETIREMENT BENEFITS (Schedule of Economic Assumptions and Impact of Change in Discount Rate on Benefit Obligation) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Dec. 29, 2019
Assumptions used to measure net pension and other postretirement cost:
Increase in Discount Rate of 0.25% - Impact on defined benefit obligation for pension benefits	$ (10,302)
Decrease in Discount Rate of 0.25% - Impact on defined benefit obligation for pension benefits	$ 10,846
Pension Benefits
Assumptions used to measure benefit obligation at end of period:
Discount rate	1.97%		2.56%
Assumptions used to measure net pension and other postretirement cost:
Discount rate	2.51%	4.40%
Expected return on plan assets	4.67%	5.50%
Other Benefits
Assumptions used to measure benefit obligation at end of period:
Discount rate	2.05%		2.77%
Assumptions used to measure net pension and other postretirement cost:
Discount rate	2.77%	4.07%