GOODWILL AND OTHER INTANGIBLE ASSETS (Details) $ in Millions	3 Months Ended		9 Months Ended				12 Months Ended
	Sep. 30, 2024 USD ($) item	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2024 USD ($) item	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Changes in the carrying amount of goodwill for each of the company's reportable segments
Number of reporting units | item	8
Impairment of goodwill			$ 0.0				$ 0.0
Changes in the carrying amount of goodwill
Beginning goodwill			8,148.2
Goodwill revised							8,148.2
Current year business combinations			33.6
Prior year business combinations			0.6
Divestiture of businesses			(305.9)
Effect of foreign currency translation			22.2
Ending goodwill	$ 7,898.7		7,898.7				8,148.2
Number of operating units				8	8
Future estimated amortization expense related to amortizable other identifiable intangible assets
Estimated expense for the remaining six-month period	73.2		73.2	$ 73.2	$ 73.2
Total amortization expense related to other intangible assets	73.3	$ 77.4	226.2			$ 229.8
Nalco Holding Company ("Nalco") | Trademarks
Changes in the carrying amount of goodwill
Impairment of indefinite life intangible asset			0.0
Carrying value of asset subject to impairment testing	1,200.0		1,200.0	$ 1,200.0	$ 1,200.0
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill			4,140.6
Goodwill revised							4,243.5
Prior year business combinations			0.6
Segment changes/Transferred to held for sale							102.9
Effect of foreign currency translation			2.8
Ending goodwill	4,246.9		4,246.9				4,140.6
Global Institutional and Specialty
Changes in the carrying amount of goodwill
Beginning goodwill			610.0
Goodwill revised							610.0
Effect of foreign currency translation			1.6
Ending goodwill	611.6		611.6				610.0
Global Healthcare and Life Sciences
Changes in the carrying amount of goodwill
Beginning goodwill			3,158.4
Goodwill revised							3,158.4
Divestiture of businesses			(305.9)
Effect of foreign currency translation			17.4
Ending goodwill	2,869.9		2,869.9				3,158.4
Global Pest Elimination
Changes in the carrying amount of goodwill
Goodwill revised							136.3
Current year business combinations			33.6
Segment changes/Transferred to held for sale							136.3
Effect of foreign currency translation			0.4
Ending goodwill	$ 170.3		170.3
Other
Changes in the carrying amount of goodwill
Beginning goodwill			$ 239.2
Segment changes/Transferred to held for sale							(239.2)
Ending goodwill							$ 239.2