EMPLOYEE BENEFIT PLANS (Pre-tax Amounts in AOCI Not Yet Recognized as Components of Net Periodic Costs) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service costs	$ (0.6)	$ (0.7)
Net actuarial (loss) gain	(8.4)	(14.5)
Total	(9.0)	(15.2)
Post Retirement Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service costs	(5.0)	(4.0)
Net actuarial (loss) gain	3.9	6.1
Total	$ (1.1)	$ 2.1