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GOODWILL AND OTHER INTANGIBLE ASSETS (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022 USD ($) segment	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Changes in the carrying amount of goodwill for each of the company's reportable segments
Number of reporting units \| segment	12
Impairment of goodwill			$ 0.0
Changes in the carrying amount of goodwill
Beginning goodwill			8,063.9
Prior year business combinations			19.9
Effect of foreign currency translation			(147.9)
Ending goodwill	$ 7,935.9		7,935.9
Future estimated amortization expense related to amortizable other identifiable intangible assets
Estimated expense for the remaining six-month period	159.0		159.0
Total amortization expense related to other intangible assets	78.7	$ 52.2	158.2	$ 116.7
Nalco Holding Company ("Nalco") \| Trade names
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
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill			4,270.1
Prior year business combinations			2.1
Effect of foreign currency translation			(79.1)
Ending goodwill	4,193.1		4,193.1
Global Institutional and Specialty
Changes in the carrying amount of goodwill
Beginning goodwill			576.5
Effect of foreign currency translation			(5.6)
Ending goodwill	570.9		570.9
Global Healthcare and Life Sciences
Changes in the carrying amount of goodwill
Beginning goodwill			2,974.2
Prior year business combinations			17.8
Effect of foreign currency translation			(60.3)
Ending goodwill	2,931.7		2,931.7
Other
Changes in the carrying amount of goodwill
Beginning goodwill			243.1
Effect of foreign currency translation			(2.9)
Ending goodwill	$ 240.2		$ 240.2