EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Retirement Benefits [Abstract]
Expected employer contribution	$ 21.0
Increase from prior year employer contributions	14.9
Components of net pension expense
Service cost	1.0	$ 1.2
Interest cost	2.0	2.8
Expected return on plan assets	(2.9)	(3.4)
Recognized net actuarial loss	0.7	1.2
Net pension expense	$ 0.8	$ 1.8