DERIVATIVES (Narrative) (Details) - bbl	Jun. 30, 2019	Dec. 31, 2018
Crude Oil and Feedstock Inventory [Member] | Fair Value Hedging [Member]
Derivative [Line Items]
Derivative, notional amount, volume	496,153	0
Intermediates and Refined Products Inventory [Member] | Fair Value Hedging [Member]
Derivative [Line Items]
Derivative, notional amount, volume	3,418,263	3,350,166
Crude Oil Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount, volume	12,167,000	5,801,000
Refined Product Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount, volume	6,481,000	1,609,000