SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Deferred Charges and Other Assets, Net) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Other non-service components of net periodic benefit cost	$ 1,109	$ (1,402)	$ (580)
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Refinery turnaround amortization period	3 years
Intangible assets estimated useful lives	1 year
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Refinery turnaround amortization period	5 years
Intangible assets estimated useful lives	10 years
Revolving Credit Facility And Senior Secured Notes [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization over life of loan	1 year
Revolving Credit Facility And Senior Secured Notes [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization over life of loan	8 years