COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Environmental liability	$ 134.2	$ 141.6
Environmental Issue [Member] \| Torrance Refinery [Member]
Loss Contingencies [Line Items]
Environmental liability	123.2	130.8
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Environmental liability	$ 125.5	$ 135.1

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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