PENSION AND OTHER POSTRETIREMENT BENEFITS (Schedule of Defined Benefit Plan Obligations and Assets) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019	Dec. 29, 2019	Dec. 30, 2018
Change in plan assets:
Fair value of plan assets, beginning of period	$ 294,589
Fair value of plan assets, end of period	246,049
Pension Benefits
Change in projected benefit obligation:
Projected benefit obligation, beginning of period	369,066	$ 157,619
Interest cost	2,039	1,467
Actuarial losses (gains)	(29,447)	4,235
Benefits paid	(4,746)	(5,611)
Other	6	0
Currency translation loss	(9,019)	0
Projected benefit obligation, end of period	327,899	157,710
Change in plan assets:
Fair value of plan assets, beginning of period	294,589	102,414
Actual return on plan assets	(37,302)	8,816
Contributions by employer	2,172	1,752
Benefits paid	(4,746)	(5,611)
Other	(438)	0
Currency translation loss	(8,226)	0
Fair value of plan assets, end of period	246,049	107,371
Funded status:
Unfunded benefit obligation, end of period	(81,850)		$ (74,477)
Amounts recognized in the Condensed Consolidated Balance Sheets at end of period:
Current liability	(11,944)		(14,967)
Long-term liability	(69,906)		(59,510)
Recognized liability	(81,850)		(74,477)
Amounts recognized in accumulated other comprehensive loss at end of period:
Net actuarial loss	68,691	50,783	58,239	$ 54,343
Other Benefits
Change in projected benefit obligation:
Projected benefit obligation, beginning of period	1,527	1,462
Interest cost	9	13
Actuarial losses (gains)	(17)	32
Benefits paid	(40)	(37)
Other	0	0
Currency translation loss	0	0
Projected benefit obligation, end of period	1,479	1,470
Change in plan assets:
Fair value of plan assets, beginning of period	0	0
Actual return on plan assets	0	0
Contributions by employer	40	37
Benefits paid	(40)	(37)
Other	0	0
Currency translation loss	0	0
Fair value of plan assets, end of period	0	0
Funded status:
Unfunded benefit obligation, end of period	(1,479)		(1,527)
Amounts recognized in the Condensed Consolidated Balance Sheets at end of period:
Current liability	(157)		(158)
Long-term liability	(1,322)		(1,369)
Recognized liability	(1,479)		(1,527)
Amounts recognized in accumulated other comprehensive loss at end of period:
Net actuarial loss	$ 74	$ (2)	$ 91	$ (34)