PENSION AND POSTRETIREMENT PLANS - Information Related to Pension and Postretirement Plans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Amounts recognized in Consolidated Balance Sheet:
Other assets	$ 46.9			$ 46.9		$ 33.0
Postretirement health care and pension benefits	(996.6)			(996.6)		$ (1,226.2)
Change in Accumulated Other Comprehensive Loss (Income):
Other comprehensive loss (income)	(33.4)	$ 18.5		(172.7)	$ (12.0)
Discontinued Operations
Projected Benefit Obligation
Service cost (a)			$ 2.5
U.S. Pension | Pension
Projected Benefit Obligation
Service cost (a)	11.2	16.5		32.8	51.9
Interest cost	13.3	17.7		38.3	52.7
U.S. Pension | U.S. Postretirement Health Care
Projected Benefit Obligation
Service cost (a)	0.2	0.3		0.6	0.9
Interest cost	0.7	0.8		2.1	2.9
International Pension | Pension
Projected Benefit Obligation
Service cost (a)	7.9	7.9		24.0	23.2
Interest cost	$ 4.4	$ 5.5		$ 13.1	$ 16.1