STOCKHOLDERS' EQUITY AND EQUITY INSTRUMENTS (Amount Reclassified from AOCI) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense									$ (68.4)	$ (62.5)	$ (52.9)
Income tax expense									22.1	8.8	60.0
Net earnings	$ 56.1	$ 10.6	$ (11.8)	$ 7.6	$ 51.0	$ 12.8	$ (7.6)	$ 12.6	62.5	68.8	$ 42.7
Amount Reclassified from AOCL
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net earnings									(1.8)	(1.6)
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense									1.0
Net earnings									(2.1)
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges | Natural gas instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Product cost									(0.9)
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges | Foreign currency contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense									(2.2)
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense										1.0
Net earnings										(1.8)
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges | Natural gas instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Product cost										0.2
Amount Reclassified from AOCL | Gains and (Losses) on Cash Flow Hedges | Foreign currency contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense										(3.0)
Amount Reclassified from AOCL | Defined Benefit Pension
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Product cost									0.4	0.2
Income tax expense									(0.1)	0.0
Net earnings									$ 0.3	$ 0.2