EMPLOYEE BENEFITS - Retirement and Post retirement costs - (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Aug. 31, 2019	May 31, 2018	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Retirement expense for continuing operations
Net pension expense			$ 4,330	$ 2,778	$ 19,386	$ 8,335
Pension plan
Retirement expense for continuing operations
Interest cost			19,596	19,788	59,713	59,365
Expected return on plan assets			(20,772)	(22,624)	(63,047)	(67,872)
Special termination benefits					6,834
Actuarial loss			6,157	6,295	17,838	18,886
Net pension expense			4,981	3,459	21,338	10,379
Proceeds from sale of real property location	$ 800	$ 4,100
Loss on sale of real property location			(600)		(600)	(200)
Post-retirement plans
Retirement expense for continuing operations
Net pension expense			$ (651)	$ (681)	$ (1,952)	$ (2,044)