ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ (310,856)	$ (325,274)	$ (325,274)
Other comprehensive income (loss) before reclassifications			157		(3,231)
Amounts reclassified from accumulated other comprehensive loss			13,168		17,649
Other comprehensive income (loss), net of tax	$ 11,685	$ 28,187	13,325	(17,407)	14,418
Ending balance	(297,531)		(297,531)		(310,856)
Foreign Currency Translation Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(88,737)	(130,019)	(130,019)
Other comprehensive income (loss) before reclassifications			3,283		41,282
Amounts reclassified from accumulated other comprehensive loss			0		0
Other comprehensive income (loss), net of tax			3,283		41,282
Ending balance	(85,454)		(85,454)		(88,737)
Total Pension and Postretirment Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(222,119)	$ (195,255)	(195,255)
Other comprehensive income (loss) before reclassifications			(3,126)		(44,513)
Amounts reclassified from accumulated other comprehensive loss			13,168		17,649
Other comprehensive income (loss), net of tax			10,042		(26,864)
Ending balance	$ (212,077)		$ (212,077)		$ (222,119)