GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Changes in the carrying amount of goodwill
Beginning goodwill	$ 7,078.0
Current year business combinations	180.4
Prior year business combinations	(0.1)
Effect of foreign currency translation	65.9
Ending goodwill	7,324.2
Future estimated amortization expense related to amortizable other identifiable intangible assets
Estimated expense remaining for the year	243.0
Total amortization expense related to other intangible assets	79.8	$ 80.2
Nalco \| Trademarks
Changes in the carrying amount of goodwill
Impairment of indefinite life intangible asset	0.0
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill	2,730.8
Current year business combinations	90.1
Prior year business combinations	(0.1)
Effect of foreign currency translation	25.4
Ending goodwill	2,846.2
Global Institutional
Changes in the carrying amount of goodwill
Beginning goodwill	1,015.3
Current year business combinations	90.3
Effect of foreign currency translation	10.1
Ending goodwill	1,115.7
Global Energy
Changes in the carrying amount of goodwill
Beginning goodwill	3,126.6
Effect of foreign currency translation	28.5
Ending goodwill	3,155.1
Other
Changes in the carrying amount of goodwill
Beginning goodwill	205.3
Effect of foreign currency translation	1.9
Ending goodwill	$ 207.2

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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