BASIS OF PRESENTATION (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative adjustment for adoption of financial instruments recognition and measurement changes	$ 0		$ 0
Defined benefit plan net periodic benefit cost other than service cost component	1,900	$ 1,300	3,700	$ 2,600
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative adjustment for adoption of financial instruments recognition and measurement changes	$ 66,234		$ 66,234