PENSION AND OTHER POSTRETIREMENT BENEFITS - Schedule of Net Defined Benefit Pension and Other Postretirement Costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Interest cost	$ 1,467	$ 1,365	$ 2,934	$ 2,731
Estimated return on plan assets	(1,349)	(1,516)	(2,698)	(3,033)
Settlement loss	1,930	0	1,930	0
Amortization of net loss	328	301	656	602
Net costs	2,376	150	2,822	300
Other Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Interest cost	13	11	26	23
Estimated return on plan assets	0	0	0	0
Settlement loss	0	0	0	0
Amortization of net loss	0	0	0	0
Net costs	$ 13	$ 11	$ 26	$ 23