CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS)
Net income including noncontrolling interest	$ 235.4us-gaap_ProfitLoss	$ 194.5us-gaap_ProfitLoss
Foreign currency translation adjustments
Foreign currency translation	(309.4)	(67.0)
Gain (loss) on net investment hedges	57.0	(3.7)
Total foreign currency translation adjustments	(252.4)	(70.7)
Derivatives and hedging instruments	7.8
Pension and postretirement benefits
Amortization of net actuarial loss and prior service cost included in net periodic pension and postretirement costs	8.0	2.6
Subtotal	(236.6)	(68.1)
Total comprehensive income (loss), including noncontrolling interest	(1.2)	126.4
Less: Comprehensive income attributable to noncontrolling interest	1.0	3.5
Comprehensive income (loss) attributable to Ecolab	$ (2.2)us-gaap_ComprehensiveIncomeNetOfTax	$ 122.9us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Current period adjustment in other comprehensive income reflecting gains or losses on foreign currency transactions that are designated as, and are effective as, hedges of a net investment in a foreign entity, net of tax effect.

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