BUSINESS SEGMENT INFORMATION - Net Sales and Income (Loss) from Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Net sales	$ 1,038.7	$ 690.5	$ 1,902.9	$ 1,524.1
Income (loss) from operations	122.5	7.4	184.0	0.3
Operating Segments | AWP
Segment Reporting Information [Line Items]
Net sales	595.2	413.9	1,071.9	925.6
Income (loss) from operations	65.2	(5.0)	91.8	(10.9)
Operating Segments | MP
Segment Reporting Information [Line Items]
Net sales	440.8	263.6	819.0	579.2
Income (loss) from operations	72.1	23.4	121.2	48.4
Corporate and Other / Eliminations
Segment Reporting Information [Line Items]
Net sales	2.7	13.0	12.0	19.3
Income (loss) from operations	$ (14.8)	$ (11.0)	$ (29.0)	$ (37.2)