GOODWILL AND OTHER INTANGIBLE ASSETS (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)
Changes in the carrying amount of goodwill
Beginning goodwill, net			$ 6,490.8
Current year business combinations			0.6
Prior year business combinations			3.3
Effect of foreign currency translation			20.8
Ending goodwill, net	$ 6,515.5		6,515.5
Goodwill expected to be tax deductible	0.0		$ 0.0
Number of Operating Segments | segment			10
Impairment of goodwill			$ 0.0
Future estimated amortization expense related to amortizable other identifiable intangible assets
2016 (Remainder: three month period)	75.0		75.0
Total amortization expense related to other intangible assets	71.9	$ 72.6	217.2	$ 218.6
Nalco | Trademarks
Changes in the carrying amount of goodwill
Impairment of indefinite life intangible asset			0.0
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	1,200.0		1,200.0
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill, net			2,560.8
Prior year business combinations			3.5
Reclassifications			3.5
Effect of foreign currency translation			8.1
Ending goodwill, net	2,575.9		2,575.9
Global Institutional
Changes in the carrying amount of goodwill
Beginning goodwill, net			662.7
Reclassifications			(0.6)
Effect of foreign currency translation			2.1
Ending goodwill, net	664.2		664.2
Global Energy
Changes in the carrying amount of goodwill
Beginning goodwill, net			3,151.5
Current year business combinations			0.6
Prior year business combinations			(0.2)
Reclassifications			(2.9)
Effect of foreign currency translation			10.2
Ending goodwill, net	3,159.2		3,159.2
Other
Changes in the carrying amount of goodwill
Beginning goodwill, net			115.8
Effect of foreign currency translation			0.4
Ending goodwill, net	$ 116.2		$ 116.2