REVENUES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Revenues	$ 4,913.2	$ 5,260.0
Deferred revenue	19.3		$ 45.1
Gasoline And Distillate [Member]
Revenues	4,230.1	4,570.4
Asphalt and Residual Oil [Member]
Revenues	215.4	207.0
Feedstocks and other [Member]
Revenues	212.3	311.3
Chemicals [Member]
Revenues	194.7	112.8
Lubricants [Member]
Revenues	$ 60.7	$ 58.5