COMMITMENTS AND CONTINGENCIES (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Environmental liability	$ 146,400,000	$ 151,900,000
Martinez Acquisition [Member]
Loss Contingencies [Line Items]
Term of Agreement	4 years
Business Combination, Contingent Consideration, Liability	$ 23,600,000	0
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Environmental liability	134,200,000	140,500,000
Environmental Issue [Member] | Torrance Refinery [Member]
Loss Contingencies [Line Items]
Environmental liability	$ 109,000,000	$ 113,700,000