EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Amortization of:
Contribution to pension plans	$ 8,000
Expected plan contributions	34,000
Pension Benefits
Amortization of:
Net pension expense	12,071	$ 6,982
Company Administered Plan | Pension Benefits
Components of net periodic benefit cost
Service cost	3,032	3,201
Interest cost	21,469	19,752
Expected return on plan assets	(22,676)	(25,834)
Amortization of:
Net actuarial loss	7,610	7,372
Prior service cost	179	145
Net pension expense	9,614	4,636
Union Administered Plan | Pension Benefits
Amortization of:
Net pension expense	2,457	2,346
U.S. | Company Administered Plan | Pension Benefits
Amortization of:
Net pension expense	11,473	7,357
Non-U.S. | Company Administered Plan | Pension Benefits
Amortization of:
Net pension expense	$ (1,859)	$ (2,721)