DERIVATIVE FINANCIAL INSTRUMENTS - Gain (Loss) on Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 4,459	$ 1,579	$ 993
Commodity forward contracts | Product cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	0	(2,130)	1,021
Foreign currency forward contracts | Loss from divestiture of grinding media business
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	0	0	(1,215)
Foreign currency forward contracts | Product sales
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	1,598	0	0
Foreign currency forward contracts | Other income (expense)
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	187	950	782
Interest rate contracts | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(64)	(64)	(423)
Cross currency swap contracts | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 2,738	$ 2,823	$ 828