Comprehensive Income (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive Income
Net income including noncontrolling interest	$ 154.5	$ 174.3	$ 374.5	$ 399.5
Other comprehensive income (loss), net of tax
Foreign currency translation		59.5	120.4	(114.8)
Derivative instruments	(6.5)	(0.6)	(16.0)	2.0
Pension and postretirement benefits	5.3	1.5	6.8	25.5
Total	(1.2)	60.4	111.2	(87.3)
Total comprehensive income, including noncontrolling interest	153.3	234.7	485.7	312.2
Less: Comprehensive income (loss) attributable to noncontrolling interest	0.3	0.1	0.7	(0.5)
Comprehensive income attributable to Ecolab	$ 153.0	$ 234.6	$ 485.0	$ 312.7

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests, if any. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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Net changes to accumulated comprehensive income during the period related to benefit plans, after tax.

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Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity, net of tax.

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This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

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Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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