ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ (325,274)	$ (288,447)	$ (288,447)
Other comprehensive income (loss) before reclassifications			1,800		(16,765)
Amounts reclassified from accumulated other comprehensive loss			12,583		6,195
Other comprehensive income (loss), net of tax	$ 31,790	$ (23,423)	14,383	(11,209)	(10,570)
Ending balance	(310,891)		(310,891)		(325,274)
Foreign Currency Translation Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(130,019)	(147,148)	(147,148)
Other comprehensive income (loss) before reclassifications			2,139		18,447
Amounts reclassified from accumulated other comprehensive loss			0		0
Other comprehensive income (loss), net of tax			2,139		18,447
Ending balance	(127,880)		(127,880)		(130,019)
Total Pension and Postretirment Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(195,255)	$ (141,299)	(141,299)
Other comprehensive income (loss) before reclassifications			(339)		(35,212)
Amounts reclassified from accumulated other comprehensive loss			12,583		6,195
Other comprehensive income (loss), net of tax			12,244		(29,017)
Ending balance	$ (183,011)		(183,011)		(195,255)
Accounting Standards Update 2018-02 [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(26,257)
Ending balance					(26,257)
Accounting Standards Update 2018-02 [Member] | Foreign Currency Translation Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(1,318)
Ending balance					(1,318)
Accounting Standards Update 2018-02 [Member] | Total Pension and Postretirment Adjustments, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ (24,939)
Ending balance					$ (24,939)