PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Detail) - Pension Plans Defined Benefit [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7,344	$ 5,874	$ 20,345	$ 18,819
Interest cost	6,574	6,951	19,629	19,406
Expected return on plan assets	(14,598)	(13,549)	(44,009)	(40,144)
Amortization of prior service cost	(105)	(24)	(230)	(75)
Amortization of unrecognized actuarial loss	4,843	2,525	12,652	9,691
Net postretirement benefit cost (income)	$ 4,058	$ 1,777	8,387	$ 7,697
Defined Benefit Plan, Plan Assets, Contributions by Employer			$ 50,000