PENSION PLANS AND RETIREMENT BENEFITS (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Pension Benefits
Service cost	$ 2.7	$ 2.7	$ 5.7	$ 5.8
Interest cost	18.8	23.7	37.5	47.3
Expected return on plans’ assets	(35.6)	(35.5)	(71.2)	(70.8)
Recognized actuarial loss	11.1	6.6	22.3	13.4
Net periodic benefit (income) cost	(3.0)	(2.5)	(5.7)	(4.3)
Other Postretirement Benefits
Service cost	0.4	0.3	0.7	0.6
Interest cost	0.3	0.5	0.7	0.9
Expected return on plans’ assets	0.0	0.0	0.0	0.0
Recognized actuarial loss	0.5	0.5	1.2	1.1
Net periodic benefit (income) cost	$ 1.2	$ 1.3	$ 2.6	$ 2.6