SIGNIFICANT ACCOUNTING POLICIES (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 segment	Dec. 31, 2013	Mar. 31, 2014
SIGNIFICANT ACCOUNTING POLICIES
Number of reporting units for which qualitative test is used	10
Impairment of goodwill	$ 0us-gaap_GoodwillImpairmentLoss
Changes in the carrying amount of goodwill
Beginning goodwill, net	6,862.9us-gaap_Goodwill	5,920.5us-gaap_Goodwill
Current year business acquisitions	33.0us-gaap_GoodwillAcquiredDuringPeriod	1,071.8us-gaap_GoodwillAcquiredDuringPeriod
Prior year acquisitions	16.8ecl_GoodwillAcquiredPriorPeriod
Business divestiture	(0.6)	(2.1)
Effect of foreign currency translation	(195.1)us-gaap_GoodwillTranslationAdjustments	(127.3)us-gaap_GoodwillTranslationAdjustments
Ending goodwill, net	6,717.0us-gaap_Goodwill	6,862.9us-gaap_Goodwill
Goodwill expected to be tax deductible	20.7	0
Nalco
Changes in the carrying amount of goodwill
Ending goodwill, net	4,500.0
Nalco \| Trademarks
Changes in the carrying amount of goodwill
Carrying value of asset subject to impairment testing	1,200.0
Impairment of indefinite life intangible asset	0	0
Champion
Changes in the carrying amount of goodwill
Ending goodwill, net	1,000.0
Champion \| Adjustment
Changes in the carrying amount of goodwill
Beginning goodwill, net			16.9
Ending goodwill, net			16.9
Net adjustment made to the preliminary purchase price allocation		37.1
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill, net	2,729.5	2,751.6
Current year business acquisitions	18.5	33.9
Prior year acquisitions	(0.1)
Business divestiture		(2.1)
Reclassifications	(28.9)
Effect of foreign currency translation	(76.8)	(53.9)
Ending goodwill, net	2,642.2	2,729.5
Global Institutional
Changes in the carrying amount of goodwill
Beginning goodwill, net	706.6	720.6
Business divestiture	(0.4)
Reclassifications	5.0
Effect of foreign currency translation	(20.0)	(14.0)
Ending goodwill, net	691.2	706.6
Global Energy
Changes in the carrying amount of goodwill
Beginning goodwill, net	3,306.2	2,325.3
Current year business acquisitions	9.9	1,037.9
Prior year acquisitions	16.9
Reclassifications	23.9
Effect of foreign currency translation	(94.8)	(57.0)
Ending goodwill, net	3,262.1	3,306.2
Other
Changes in the carrying amount of goodwill
Beginning goodwill, net	120.6	123.0
Current year business acquisitions	4.6
Business divestiture	(0.2)
Effect of foreign currency translation	(3.5)	(2.4)
Ending goodwill, net	$ 121.5	$ 120.6

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount after accumulated impairment loss of an asset representing 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 loss from the write-down 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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