DEFERRED CHARGES AND OTHER ASSETS, NET (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	$ 9,593	$ 9,440
Deferred turnaround costs, net	560,403	302,919
Catalyst	131,019	114,788
Linefill	19,485	19,485
Pension plan assets	42,452	51,636
Intangible assets, net	537	577
Other	16,435	5,158
Total deferred charges and other assets, net	779,924	504,003
Amortization expense	143,978	105,547	$ 102,636
Intangible Assets, Net [Abstract]
Gross amount	3,996	3,996
Accumulated amortization	(3,459)	(3,419)
Net amount	$ 537	$ 577