Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Weighted-average common shares outstanding Weighted Average Number of Shares Outstanding, Diluted [Abstract] Trading Arrangement: Trading Arrangement [Axis] Maximum Maximum [Member] Number of sub operating segments Number Of New Operating Segments Number of sub-operating segments. Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] Title of 12(b) Security Title of 12(b) Security Carrying Amount Reported Value Measurement [Member] Subsequent Event Subsequent Event [Member] Acquisitions and investments in affiliates, net of cash acquired Payments to Acquire Businesses and Interest in Affiliates Document Fiscal Year Focus Document Fiscal Year Focus Increases due to billings excluding amounts recognized as revenue during the period ended Contract with Customer, Liability, Increase Due to Invoices Issued Amount of increase in obligation due to invoices issued, excluding amount recognized as revenue during the period. Gross amounts offset in the Consolidated Balance Sheets Derivative Liability, Subject to Master Netting Arrangement, Asset Offset Acquisition and integration activities Business Combination, Acquisition-Related Cost, Expense Adjustment to Compensation, Amount Adjustment to Compensation Amount Segment Reporting [Abstract] Segment Reporting [Abstract] Restructuring Plan [Axis] Restructuring Plan [Axis] Nalco Holding Company ("Nalco") Nalco Holding Company [Member] Represents the acquisition of Nalco by the entity. Common stock Common Stock, Value, Issued Compensation and benefits Employee-related Liabilities, Current Trademarks Trademarks [Member] Schedule of Long-Term Debt Obligations Including Current Maturities Schedule of Long-Term Debt Instruments [Table Text Block] Other Other Assets, Miscellaneous, Noncurrent PENSION AND POSTRETIREMENT PLANS Retirement Benefits [Text Block] Restatement Determination Date Restatement Determination Date Cash collateral pledged Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Contract assets Contract with Customer, Asset, after Allowance for Credit Loss Derivative Instrument [Axis] Derivative Instrument [Axis] CoolIT Systems CoolitSystems [Member] Represents information pertaining to CoolIT Systems. Beginning balance Ending balance Accounts Receivable, Allowance for Credit Loss Intangible assets not subject to amortization Intangible Asset, Excluding Goodwill, Indefinite-Lived [Abstract] Property and other assets sold Proceeds from Sale of Productive Assets Amendment Flag Amendment Flag Changes in the carrying amount of goodwill for each of the company's reportable segments Goodwill [Line Items] Current liabilities Liabilities, Current [Abstract] Bad debt expense Accounts Receivable, Credit Loss Expense (Reversal) Schedule of notional values of outstanding derivatives Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Number of locations for environmental assessments and remediation Number of Locations for Environmental Assessments and Remediation Represents the number of locations for environmental assessments and remediation. Other Other Sundry Liabilities, Current Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Changes in Currency Rates ComparabilityAdjustmentsForChangesInForeignCurrencyTranslationRate [Member] Represents information pertaining to comparability adjustments for changes in foreign currency translation rates. Disposal Group Classification [Axis] Disposal Group Classification [Axis] Derivative & Hedging Instruments AOCI, Derivative Qualifying as Hedge, Excluded Component, Parent [Member] Loss Contingencies [Table] Loss Contingencies [Table] Amortization Amortization Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax [Abstract] EARNINGS ATTRIBUTABLE TO ECOLAB PER COMMON SHARE ("EPS") EARNINGS ATTRIBUTABLE TO ECOLAB PER COMMON SHARE ("EPS") [Abstract] EARNINGS ATTRIBUTABLE TO ECOLAB PER COMMON SHARE ("EPS") Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Property, plant and equipment, net Property, Plant, and Equipment [Abstract] Entity Address, State or Province Entity Address, State or Province Number of plaintiffs having claims Loss Contingency, Number of Plaintiffs PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value per share (in dollars per share) Common Stock, Par or Stated Value Per Share Total foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Assets Assets, Fair Value Disclosure [Abstract] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Restructuring charges incurred, after tax Restructuring and Related Cost Incurred Cost Net of Tax Represents the after-tax restructuring charge charged against the accrued restructuring reserves or earnings, if not previously accrued, during the period for the specified type of restructuring cost. Other intangible assets, net Total Intangible Asset, Excluding Goodwill, after Accumulated Amortization Derivative notional value Derivative, Notional Amount Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Contract assets Contract with Customer, Asset, after Allowance for Credit Loss, Current Retirement Benefits [Abstract] Retirement Benefits [Abstract] Business combination and integration related costs, after tax Business Combination Integration Related Costs, Net of Tax Costs incurred to effect a business combination which have been expensed during the period, net of tax. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. 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Loss contingencies Loss Contingencies [Line Items] Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Customer relationships Customer Relationships [Member] Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Entity Address, City or Town Entity Address, City or Town Defined Benefit Plan Disclosure Defined Benefit Plan Disclosure [Line Items] Outstanding commercial paper Commercial Paper SPECIAL (GAINS) AND CHARGES Special Gains and Charges [Text Block] The aggregate amount of other nonrecurring expenses, not previously categorized, that are infrequent in occurrence or unusual in nature. Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] International Pensions Foreign Plan [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Class of Stock [Axis] Class of Stock [Axis] Public notes Public Notes [Member] Public Notes. Net intangible assets subject to amortization Intangible Asset, Finite-Lived, after Accumulated Amortization Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Accounts receivable Accounts Receivable, before Allowance for Credit Loss Inventories Inventory, Net [Abstract] Level 2 Fair Value, Inputs, Level 2 [Member] Accumulated amortization Intangible Asset, Finite-Lived, Accumulated Amortization Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Maximum borrowing capacity under the credit agreement Line of Credit Facility, Maximum Borrowing Capacity Subtotal Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Long-term debt, current maturities Long-Term Debt, Current Maturities Consolidated Net Sales Revenue Benchmark [Member] United States United States UNITED STATES Other Other Restructuring [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Ten year 2025 senior nots Ten Year 2025 Senior Notes [Member] Represents information pertaining to ten-year 2025 senior notes. Derivatives and hedging instruments Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Ten year 2020 senior notes, maturing in 2031 Ten Year 2020 Senior Notes Maturing 2031 [Member] Represents the ten year 2020 senior notes that mature in 2031. Non-Controlling Interest Noncontrolling Interest [Member] Domestic Plan Domestic Plan [Member] Comparability Adjustments [Domain] Comparability Adjustments [Domain] Components of comparability adjustments. Amount recognized in AOCI Other Comprehensive Income (Loss), before Tax Other Special (Gains) and Charges, Other Represents the amount of other charges in special gains and charges in the statement of operations. Number of shares reacquired through the open market (in shares) Treasury Stock, Acquired Through Open Market Number of shares that have been repurchased through the open market during the period, and are being held in treasury. Document Period End Date Document Period End Date Changes in operating assets and liabilities, net of effect of acquisitions: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Cash used for investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Aggregate principal amount Debt Instrument, Face Amount SHAREHOLDERS' EQUITY Equity [Text Block] Restructuring charges incurred to date, pre-tax Restructuring and Related Cost, Cost Incurred to Date Security Exchange Name Security Exchange Name Debt instrument, term Debt Instrument, Term Treasury stock Treasury Stock, Common, Value Debt instrument, interest rate, effective percentage Debt Instrument, Interest Rate, Effective Percentage Purchase price of expected business acquisition Business Combination, Price of Acquisition, Expected Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Dispensing and monitoring equipment Dispensing and Monitoring Equipment, Gross Amount before accumulated depreciation of tangible personal property used for dispensing and monitoring purposes. FIFO cost to LIFO cost difference Inventory, LIFO Reserve Accumulated other comprehensive loss Total Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Consolidation Items [Domain] Consolidation Items [Domain] Contributions to plan Payment for Pension Benefits Operating lease liabilities Operating Lease, Liability, Current Interest payable Interest Payable, Current Summarized activity in the allowance for expected credit losses Accounts Receivable, Allowance for Credit Loss [Table Text Block] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Restructuring charges incurred to date, after-tax Restructuring and Related Cost, Cost Incurred to Date, Net of Tax Amount of costs incurred to date for the specified restructuring cost, net of tax. EARNINGS ATTRIBUTABLE TO ECOLAB PER COMMON SHARE ("EPS") Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings attributable to Ecolab per common share Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Eleven year 2021 senior notes Eleven Year 2021 Senior Notes [Member] This member stands for Eleven Year 2021 Senior Notes. Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Total liabilities Liabilities Trading Symbol Trading Symbol Service and lease sales Service And Lease [Member] Service and lease. Geographical [Domain] Geographical [Domain] Trade names Intangible Asset, Excluding Goodwill, Indefinite-Lived Schedule of Interest Expense and Interest Income Interest Income and Interest Expense Disclosure [Table Text Block] Capital expenditures Payments to Acquire Property, Plant, and Equipment Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Consideration transferred to sellers Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred Income taxes Accrued Income Taxes, Current Schedule of the acquisition date fair value of net assets acquired Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block] Company Selected Measure Name Company Selected Measure Name Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Pension and postretirement plan (income) expense, net Pension and Other Postretirement Benefits Cost (Reversal of Cost) Gain after tax Gain (Loss) on Disposition of Assets, Net of Tax Gain (Loss) on Disposition of Assets, Net of Tax Intangible Asset, Indefinite-Lived [Table] Intangible Asset, Indefinite-Lived [Table] Divestiture of businesses, net of cash divested Proceeds from Divestiture of Businesses, Net of Cash Divested Accumulated Defined Benefit Plans Adjustment Attributable to Parent Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] CHF Switzerland, Francs BALANCE SHEETS INFORMATION BALANCE SHEETS INFORMATION [Abstract] BALANCE SHEETS INFORMATION Compensation Amount Outstanding Recovery Compensation Amount Dividends payable Dividends Payable, Current Business Acquisitions and Investment Business Acquisitions and Investment [Member] Business Acquisitions and Investment Individual: Individual [Axis] BALANCE SHEETS INFORMATION Intangible Asset, Indefinite-Lived [Line Items] Diluted (in shares) Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of revenue Disaggregation of Revenue [Line Items] Cross-currency swap derivative contracts Cross-currency swap derivative contracts Cross Currency Interest Rate Contract [Member] Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Pension and postretirement benefits Liability, Defined Benefit Plan, Noncurrent Disposal Group Name [Domain] Disposal Group Name [Domain] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Deferred income taxes Deferred Income Taxes and Tax Credits Commercial paper Commercial Paper [Member] DERIVATIVES AND HEDGING TRANSACTIONS Derivative Instruments and Hedging Activities Disclosure [Text Block] Ten year 2016 senior notes Ten Year 2016 Senior Notes [Member] Represents the ten year 2016 senior notes. Business combination, goodwill, expected tax deductible, amount Business Combination, Goodwill, Expected Tax Deductible, Amount Other technologies Other Technology [Member] Details pertaining to intangible assets related to other technology not separately identified. Short-term debt Short-Term Debt Other Nonrecurring Income (Expense) by Income Statement Location [Table] Other Nonrecurring Income (Expense) by Income Statement Location [Table] A table or schedule providing information pertaining to non-recurring income and expenses of the entity. Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Estimated settlement Loss Contingency, Estimated Settlement Amount Reflects the estimated settlement amount of loss from the specified contingency as of the balance sheet date. Other intangibles Other Intangible Assets [Member] Maximum period for hedged transactions Cash Flow Hedge, Hedging Exposure, Maximum Period Thirty year 2016 senior notes Thirty Year 2016 Senior Notes [Member] Represents the thirty year 2016 senior notes due 2046. Award Timing Predetermined Award Timing Predetermined [Flag] Treasury Stock Treasury Stock, Common [Member] Schedule of other comprehensive income information related to the Company's derivatives and hedging instruments and pension and postretirement benefits Comprehensive Income (Loss) [Table Text Block] Intangible Asset, Goodwill and Other [Abstract] Intangible Asset, Goodwill and Other [Abstract] India, Middle East and Africa India, Middle East and Africa [Member] Regions of India, Middle East and Africa. Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Total debt Debt and Lease Obligation Level 1 Fair Value, Inputs, Level 1 [Member] Derivative asset Derivative Asset, Noncurrent Effective income tax rate (as a percent) Effective Income Tax Rate Reconciliation, Percent Thirty-four year 2021 senior notes Thirty Four Year 2021 Senior Notes [Member] Represent the thirty four year 2021 senior notes that mature in 2055 Intangible Asset, Indefinite-Lived, Class [Domain] Intangible Asset, Indefinite-Lived, Class [Domain] Effect of dilutive stock options and units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Gross value of derivatives Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement All Executive Categories All Executive Categories [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] U.S. commercial paper program US Commercial Paper Program [Member] Represents the entity's U.S. commercial paper program. Number of acquisitions Number of Acquisitions Total number of acquisitions during the period. Long-term debt, including current maturities Long-Term Debt, Fair Value Net periodic pension and postretirement health care benefit costs Schedule of Net Benefit Costs [Table Text Block] Schedule of revaluation gains and losses on euro notes and cross-currency swap derivative Schedule of Net Investment Hedges, Statements of Financial Performance and Financial Position, Location [Table Text Block] Depreciation Depreciation Scenario [Domain] Scenario [Domain] Operating lease assets Operating Lease, Right-of-Use Asset Schedule of Balance Sheet Information Selected Balance Sheet Information [Table Text Block] Disclosures related to selected balance sheet information. Concentration Risk Type [Domain] Concentration Risk Type [Domain] Accounting Changes and Error Corrections [Abstract] Accounting Changes and Error Corrections [Abstract] Reclassification Restructuring Reserve, Reclassification Amount of reclassification represents an increase to the restructuring reserve. Schedule of computations of the basic and diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Other Accounts Receivable, Allowance for Credit Loss, Other Adjustments Amount of other adjustments for expected credit loss on accounts receivable. Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Multi Currency Revolving Credit Facility Multi Currency Revolving Credit Facility [Member] Represents the multi-currency revolving credit facility which matures in April 2026. Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Long-term debt, current maturities Long-Term Debt and Lease Obligation, Current Unrecognized pension and postretirement benefit expense, net of tax Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax OPERATING SEGMENTS Segment Reporting [Text Block] Minimum Minimum [Member] Amount outstanding under the credit agreement Long-Term Line of Credit Acquisition-related liabilities and contingent consideration Business Combination Acquisition Related Liabilities and Contingent Consideration Business Combination Acquisition Related Liabilities and Contingent Consideration Dividends paid Payments of Ordinary Dividends, Common Stock Expiration Date Trading Arrangement Expiration Date Global Life Sciences Global Healthcare And Life Sciences [Member] Represents a reportable segment consisting of pharmaceutical, personal care, infection and containment control solutions. Hedging Relationship [Axis] Hedging Relationship [Axis] Gross value of derivatives Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement Schedule of principal activities, separated by reportable segments and geographic region Disaggregation of Revenue [Table Text Block] Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Location, Statement of Income, Balance [Axis] Location, Statement of Income, Balance [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Total equity Balance, beginning Balance, Ending Equity, Including Portion Attributable to Noncontrolling Interest Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Global Institutional & Specialty Global Institutional [Member] Represents a reportable segment consisting of the water treatment programs and process applications, and wash process solutions. Estimated possible loss Loss Contingency, Estimate of Possible Loss Business Combination [Line Items] Business Combination [Line Items] Total expense (benefit) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Common stock, shares authorized Common Stock, Shares Authorized Computations of the basic and diluted earnings attributable to Ecolab per share amounts Earnings Per Share Reconciliation [Abstract] OTHER COMPREHENSIVE INCOME (LOSS) INFORMATION Accumulated Other Comprehensive Income (Loss) [Line Items] Common stock shares issued not disclosed Common Stock Shares Issued Not Disclosed N/A Schedule of financial information for each of the entity's reportable segments, including the impact of the preceding changes on previously reported full year 2024 net sales and operating income Schedule of Segment Reporting Information, by Segment, Including Changes for Comparability of Reportable Segments [Table Text Block] Tabular disclosure of the profit or loss and total assets for each reportable segment, including disclosure of changes for comparability of reportable segments. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss. Exercise Price Award Exercise Price Segment Changes ComparabilityAdjustmentsForSegmentChanges [Member] Represents information pertaining to comparability adjustments for segment changes. Restructuring Cost [Table] Restructuring Cost [Table] OPERATING SEGMENTS Segment Reporting [Line Items] Special (gains) and charges Special Gains and Charges [Line Items] Special Gains and Charges [Line Items] Document Quarterly Report Document Quarterly Report Derivative Assets Derivative Asset [Abstract] Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Segments [Domain] Segments [Domain] Europe Europe [Member] Interest rate swap agreements Interest rate swap agreements Interest Rate Swap [Member] Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Measurement period adjustments Intangible Asset, Finite-Lived, Measurement Period Adjustment DEBT AND INTEREST Debt Disclosure [Text Block] Scenario [Axis] Scenario [Axis] Allowance for expected credit losses and other accruals Accounts Receivable, Allowance for Credit Loss and Other Accruals Amount of allowance for credit loss on accounts receivable, classified as current, including other accruals. Disposal Group Classification [Domain] Disposal Group Classification [Domain] Derivative Liabilities Derivative Liability [Abstract] Net tangible assets (liabilities) acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Tangible Assets The amount of tangible assets recognized as of the acquisition date. Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Restructuring liability Restructuring liability, at end of period Restructuring Reserve Business Combination [Table] Business Combination [Table] Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Foreign currency forward contracts Foreign Currency Contract, Asset, Fair Value Disclosure Derivative (gain) loss reclassified from AOCI into income, net of tax Other Comprehensive Income Loss Reclassification Adjustments From Aoci On Derivatives Net Of Tax Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss) Ovivo's Electronics Ovivo Electronics [Member] Represents information pertaining to Ovivo's Electronics. Buildings and leasehold improvements Buildings and Improvements, Gross Adoption Date Trading Arrangement Adoption Date Other Restructuring Plan Other Restructuring Plan [Member] Other Restructuring Plan Euro Euro Member Countries, Euro Interest rate (as a percent) Debt Instrument, Interest Rate, Stated Percentage Cash dividends declared Dividends, Common Stock, Cash Total Ecolab shareholders’ equity Equity, Attributable to Parent Forward-starting interest rate lock contracts Interest Rate Lock Contract [Member] Represents information pertaining to interest rate lock contract. Other (income) expense Nonoperating Income (Expense) Disposal Group, Disposed of by Sale, Not Discontinued Operations Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Restructuring Type [Axis] Restructuring Type [Axis] Pension Assets for Plan Benefits, Defined Benefit Plan Recorded expense and accrual Restructuring Charges, Including Accrual Adjustment Amount of restructuring charges, including accrual adjustment. ASSETS Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Other current liabilities Other Liabilities, Current [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Professional services Professional Fees Insider Trading Policies and Procedures [Line Items] Prior year business combinations, goodwill adjustments Prior year business combinations Goodwill, Measurement Period Adjustment Restructuring charge expected to be incurred, after tax Restructuring and Related Activities, Cost Expected to be Incurred, Net of Tax Represents the after-tax restructuring charge, which the entity expects to incur over a period under the restructuring plan and other cost savings actions. Other, net Proceeds from (Payment for) Other Financing Activity Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Derivative liability Derivative Instruments and Hedges, Liabilities Common stock, shares authorized to be repurchased (in shares) Share Repurchase Program, Authorized, Number of Shares Acquisition related net tangible assets adjustments Net Tangible Assets, Purchase Accounting Adjustments Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from net tangible assets acquired in a business combination that are not individually identified and separately recognized. Selling, general and administrative expenses SG&A Selling, General and Administrative Expense Selling, General and Administrative Expense BALANCE SHEETS INFORMATION Supplemental Balance Sheet Disclosures [Text Block] Amount of (loss) gain reclassified from AOCI to income Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion Patents Patents [Member] Business Combination [Domain] Business Combination [Domain] Type of Restructuring [Domain] Type of Restructuring [Domain] Interest expense, net Interest expense Interest Income (Expense), Nonoperating Operating Lease, Lease Income [Abstract] Operating Lease, Lease Income [Abstract] Valued at 2026 Fixed Currency Rates Valued At 2026 Fixed Currency Rates [Member] Represents information pertaining to valued at 2026 fixed currency rates. COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Operating lease revenue Operating Lease, Lease Income Construction in progress Construction in Progress, Gross Number of operating segments Number of Operating Segments Anti-dilutive securities excluded from the computation of diluted EPS (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Discounts and rebates Accrued Marketing Costs, Current Schedule of Changes in Carrying Amount of Goodwill Goodwill [Table Text Block] Entity Central Index Key Entity Central Index Key Accumulated depreciation Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Net periodic benefit costs Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] CNY China, Yuan Renminbi Additional paid-in capital Additional Paid in Capital, Common Stock All Adjustments to Compensation All Adjustments to Compensation [Member] Segment Reporting, Reconciling Item, Corporate Nonsegment Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] Equity [Abstract] Business Combination [Axis] Business Combination [Axis] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] One Ecolab/Other restructuring Restructuring charges incurred, pre-tax Restructuring and Related Cost, Incurred Cost Cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Six year 2021 senior notes Six Year 2021 Senior Notes [Member] This member stands for Six Year 2021 Senior Notes. Net cash payments Cash Activity for Restructuring Amount of cash activity as the result of exit or disposal activities. May include cash proceeds, but excludes payments associated with a discontinued operation or an asset retirement obligation. Income Statement [Abstract] Income Statement [Abstract] Document Transition Report Document Transition Report Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Derivatives designated as hedging instruments Designated as Hedging Instrument [Member] Deferred income taxes Deferred Income Tax Assets, Net Restructuring Plan [Domain] Restructuring Plan [Domain] Finance lease obligations and other Finance Lease, Liability, Noncurrent Units Tested For Impairment Units Tested For Impairment [Member] Units Tested For Impairment Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Postretirement Benefits Postretirement Health Coverage [Member] Comparability Adjustments [Axis] Comparability Adjustments [Axis] Information by comparability adjustments. City Area Code City Area Code Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] AOCI (Loss) AOCI Attributable to Parent [Member] Geographic Concentration Risk Geographic Concentration Risk [Member] Seven Year 2026 Fixed Rate Senior Notes 5.15% Effective Rate 5.17% Seven year 2026 senior notes Seven Year 2026 Fixed Rate Senior Notes 5.15% Effective Rate 5.17% [Member] Seven Year Fixed Rate Notes 5.15% Effective Rate 5.17% All Individuals All Individuals [Member] Corporate Corporate Segment [Member] Name Forgone Recovery, Individual Name Previously Reported Previously Reported [Member] Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Maximum borrowing capacity, commercial paper Commercial Paper Maximum Borrowing Capacity Maximum borrowing capacity under the entity's commercial paper program. Statement Statement [Line Items] Total assets Assets Defined Benefit Plan [Table] Defined Benefit Plan [Table] Business Combination [Abstract] Business Combination [Abstract] Remaining net tax expense (benefit) Tax Adjustments, Settlements, and Unusual Provisions Amortization of prior service benefit Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Operating Segments Operating Segments [Member] Interest expense Interest Expense, Nonoperating Amount recognized in AOCI Other Comprehensive Income (Loss), before Reclassifications, before Tax Impairment of indefinite life intangible asset Intangible Asset, Excluding Goodwill, Indefinite-Lived, Impairment Loss Other assets Increase (Decrease) in Other Operating Assets PEO PEO [Member] Restructuring and related special charges, pre-tax Restructuring And Related Special Charges Expected Cost1 Amount expected to be recognized in earnings for the specified special charges restructuring cost. Gross amounts offset in the Consolidated Balance Sheets Derivative Asset, Subject to Master Netting Arrangement, Liability Offset Measurement Basis [Axis] Measurement Basis [Axis] Other liabilities Other Liabilities, Noncurrent Goodwill Beginning goodwill Ending goodwill Goodwill Retirement Plan Type [Axis] Retirement Plan Type [Axis] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Current year business combinations Goodwill, Acquired During Period Reporting Unit [Axis] Reporting Unit [Axis] Revenue recognized in the period from: Amounts included in the contract liability at the beginning of the year Contract with Customer, Liability, Revenue Recognized Subsequent Event Type [Domain] Subsequent Event Type [Domain] Retained Earnings Retained Earnings [Member] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Finance lease obligations and other Other Long Term Debt [Member] Represents other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer. Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Schedule of carrying amount and estimated fair value of long-term debt Fair Value, by Balance Sheet Grouping [Table Text Block] Diluted (in dollars per share) Diluted EPS (in dollars per share) Earnings Per Share, Diluted Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Entity Current Reporting Status Entity Current Reporting Status Cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss [Abstract] Total Shareholder Return Amount Total Shareholder Return Amount Global Pest Elimination Global Pest Elimination [Member] Represents a reportable segment consisting of global pest elimination. Global surgical solutions business Global Surgical Solutions Business [Member] Represents information pertaining to global surgical solutions business. Cash Flow Hedging [Member] Cash Flow Hedging [Member] Liabilities Liabilities, Fair Value Disclosure [Abstract] Total amortization expense related to other intangible assets Intangible Asset, Finite-Lived, Amortization Expense Cumulative translation, net of tax Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Adjustments to reconcile net income to cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Write-offs Accounts Receivable, Allowance for Credit Loss, Writeoff Property, plant and equipment, net Total Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Net sales Net Sales Revenue from Contract with Customer, Excluding Assessed Tax Schedule of impact on AOCI and earnings from derivative contracts qualified as cash flow hedges Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Product and equipment sales Product And Equipment [Member] Product and equipment. Interest cost on benefit obligation Defined Benefit Plan, Interest Cost Taxes payable, other than income Taxes Payable Other than Income Carrying value as of the balance sheet date of obligations incurred and payable for real, property taxes, and statutory sales and use tax (including value added tax). Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Restructuring activity Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Pension and postretirement benefits amortization of losses and prior period service credits, net and settlement charges, reclassified from AOCI into income, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax Net value of derivatives Derivative Asset Intangible Asset, Finite-Lived, Class [Axis] Intangible Asset, Finite-Lived, Class [Axis] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] GOODWILL AND OTHER INTANGIBLE ASSETS Intangible Asset and Goodwill [Text Block] Underlying Securities Award Underlying Securities Amount Schedule of new accounting pronouncements Accounting Standards Update and Change in Accounting Principle [Table Text Block] Comprehensive income attributable to noncontrolling interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Fair Value Estimate of Fair Value Measurement [Member] REVENUES Revenue from Contract with Customer [Text Block] CONSOLIDATED FINANCIAL INFORMATION CONSOLIDATED FINANCIAL INFORMATION [Abstract] CONSOLIDATED FINANCIAL INFORMATION Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Foreign currency forward contracts Foreign Currency Contracts, Liability, Fair Value Disclosure Prepaid assets Prepaid Expense, Current Other, net Payment for (Proceeds from) Other Investing Activity Inventories Increase (Decrease) in Inventories Gain (loss) on net investment hedges Total revaluation gain (loss), net of tax Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax Segment Reporting [Table] Segment Reporting [Table] Contributions anticipated to be made during the remainder of 2026 Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year Special (gains) and charges Special (gains) and charges Special (gains) and charges subtotal Other Nonrecurring (Income) Expense INVESTING ACTIVITIES Cash Provided by (Used in) Investing Activity, Continuing Operation [Abstract] Other current assets Total Other Assets, Current OPERATING ACTIVITIES Cash Provided by (Used in) Operating Activity, Continuing Operation [Abstract] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Amount of gain (loss) recognized in income Derivative, Gain (Loss) on Derivative, Net Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Operating income Operating Income Operating Income (Loss) Operating Income (Loss) Asia Pacific Asia Pacific [Member] Current Fiscal Year End Date Current Fiscal Year End Date Other special gains and charges, after-tax Special Gains and Charges, Other, After Tax The amount of other charges, after tax, in special gains and charges in the statement of operations. Sale of global surgical solutions business Gain (Loss) on Disposition of Business Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Derivative [Line Items] Derivative [Line Items] ACQUISITIONS Business Combination [Text Block] Restructuring charge expected to be incurred, pre-tax Restructuring and Related Cost, Expected Cost Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Service cost Defined Benefit Plan, Service Cost Stock options and awards Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture Net repayments of commercial paper and notes payable Proceeds from (Repayments of) Short-Term Debt Machinery and equipment Machinery and Equipment, Gross Interest expense, net (b) Interest expense, net Interest (income) expense, net Interest Expense, Net The cost of borrowed funds accounted for as interest that was charged against earnings during the period net of income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Amount of gain (loss) reclassified from AOCI to income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Restructuring and related activities special charges, after tax Restructuring And Related Activities Special Charges Expected To Be Incurred Net Of Tax Represents the after-tax restructuring charge, which the entity expects to incur over a period under the restructuring plan, special charges and other cost savings actions. 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Resulting in a gain Gain (Loss) on Disposition of Assets Goodwill [Table] Goodwill [Table] Other Other Assets, Miscellaneous, Current Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Foreign currency translation Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Long-term debt borrowings Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number Canada CANADA Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Net Investment Hedging Net Investment Hedging [Member] Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Commitments and contingencies (Note 16) Commitments and Contingencies Other intangible assets, gross Intangible Asset, Finite-Lived, before Accumulated Amortization Property, plant and equipment, gross Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Greater China CHINA Tax impact Other Comprehensive Income (Loss), Tax Changes in the carrying amount of goodwill Goodwill [Roll Forward] LIABILITIES AND EQUITY Liabilities and Equity [Abstract] Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Trade names Trade Names [Member] Schedule of the carrying amount and estimated fair value of assets and liabilities measured on recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Inventories Total Inventory, Net All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Reacquired shares (in shares) Treasury Stock, Shares, Acquired PEO Name PEO Name Ten year 2017 senior notes Ten Year 2017 Senior Notes [Member] Represents the ten year 2017 senior notes that mature in 2027. Geographical [Axis] Geographical [Axis] Contract liability as of beginning of the year Contract liability as of end of period Contract with Customer, Liability Special (gains) and charges Schedule of Unusual or Infrequent Items, or Both [Table Text Block] Ten Year Fixed Rate Notes 5.35% Effective Rate 5.39% Ten year 2026 senior notes Ten Year 2026 Fixed Rate Senior Notes 5.35% Effective Rate 5.39% [Member] Ten Year 2026 Fixed Rate Senior Notes 5.35% Effective Rate 5.39% Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Share based compensation, excess tax benefits Share-Based Payment Arrangement, Expense, Tax Benefit Reacquired shares Treasury Stock, Value, Acquired, Cost Method Construction loan payable Construction Loan Payable [Member] Cash collateral received Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Environmental matters Accrual for Environmental Loss Contingencies Disclosure [Abstract] Accounts payable Increase (Decrease) in Accounts Payable Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code One Ecolab One Ecolab Initiative Program One Ecolab Initiative Program [Member] Represents information pertaining to one Ecolab initiative program. Services from professionals, net of tax Professional Fees, After Tax Amount of fee charged for services from professionals, net of tax. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Schedule of derivative and pension and postretirement benefit amounts reclassified from AOCI into income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] CONSOLIDATED FINANCIAL INFORMATION Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Total comprehensive income, including noncontrolling interest Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Debt Instrument [Axis] Debt Instrument [Axis] Reporting Unit [Domain] Reporting Unit [Domain] Share-based compensation expense Share-Based Payment Arrangement, Noncash Expense Land Land Interest expense, after tax Interest Income (Expense), Nonoperating, After Tax Interest Income (Expense), Nonoperating, After Tax Disposal Group Name [Axis] Disposal Group Name [Axis] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Schedule of Gross fair value and net value of the company's outstanding derivative assets and liabilities Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Basic (in dollars per share) Earnings Per Share, Basic Raw materials and parts Inventory, Raw Materials, Gross Contract liability Contract with Customer, Liability, Current Reacquired shares Payments for Repurchase of Common Stock Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Total long-term debt Long-Term Debt, Excluding Current Maturities Award Type Award Type [Axis] Amount of gain (loss) recognized in income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Cumulative amount of the fair value hedging adjustment included in the carrying amount of the hedged liabilities Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) Deferred financing costs Payments of Financing Costs Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts receivable, net Total Accounts Receivable, after Allowance for Credit Loss, Current Special charges to date Special Charges To Date The amount of non-restructuring special charges incurred to date. Retained earnings Retained Earnings (Accumulated Deficit) Restructuring and Related Activities [Abstract] Schedule of Short-Term Debt Obligations Schedule of Short-Term Debt [Table Text Block] Product and Service [Axis] Product and Service [Axis] Other current assets Other Current Assets [Abstract] No definition available. All Currencies [Domain] All Currencies [Domain] Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Goodwill, reporting units Goodwill, Reporting Unit, Number Prior Year Plans Prior Year Plans [Member] Information pertaining to restructuring plans initiated prior to 2018. Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Pension Plan Pension Plan [Member] Sale of global surgical solutions business Special Gains and Charges, Gain (Loss) on Sale of Investment The amount of the gain or (loss) on the sale of investment that was recorded in special gains and charges in the statement of operations. Common Stock Common Stock [Member] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Schedule of operating lease revenue Operating Lease, Lease Income [Table Text Block] Employee Severance Employee Severance [Member] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Thirty year 2021 senior notes Thirty Year 2021 Senior Notes [Member] This member stands for Thirty Year 2021 Senior Notes. Percentage of consolidated sales Concentration Risk, Percentage Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Three year 2025 senior notes Three Year 2025 Senior Notes [Member] Represents the three year 2025 senior notes. Effect of foreign currency translation and other Goodwill, Foreign Currency Translation, Gain (Loss) Equity Awards Adjustments Equity Awards Adjustments [Member] Hedging Relationship [Domain] Hedging Relationship [Domain] Total liabilities and equity Liabilities and Equity Allowance for doubtful accounts, returns and credits Allowance for Doubtful Accounts Returns Credits This element represents the portion of the allowance for doubtful accounts receivable representing the expected return of products shipped and credits related to pricing or quantities shipped. Employee Stock Option Share-Based Payment Arrangement, Option [Member] Short-term debt Total Debt, Current (Gains) losses reclassified from AOCI into income Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Carrying amount and fair value of financial instruments Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Noncontrolling interest Equity, Attributable to Noncontrolling Interest Notes payable Notes Payable, Other Payables [Member] Segments [Axis] Segments [Axis] Other liabilities Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Schedule of amounts on the Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Tabular List, Table Tabular List [Table Text Block] Intangible assets subject to amortization Intangible Asset, Finite-Lived, after Accumulated Amortization [Abstract] Ecolab Shareholders' Equity Parent [Member] Intangible asset, finite-lived, estimated amortization expense, remainder of fiscal year Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year Taxes receivable Income Taxes Receivable, Current Name Awards Close in Time to MNPI Disclosures, Individual Name Equity Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Other assets Assets, Noncurrent [Abstract] Valued at 2025 Fixed Currency Rates Valued at 2025 Fixed Currency Rates [Member] Information pertaining to Valued at 2025 Fixed Currency Rates. Five Year Fixed Rate Notes 4.80% Effective Rate 4.84% Five Year 2026 senior notes Five Year 2026 Senior Notes Fixed Rate 4.80% Effective Rate 4.84% [Member] Five Year 2026 Senior Notes Number of shares that have been repurchased through the exercise of stock options and vesting of stock awards (in shares) Treasury Stock, Acquired Through Exercise of Stock Options and Vesting of Stock Awards, Number of Shares Number of shares that have been repurchased through the exercise of stock options and vesting of stock awards. Fair value company's outstanding derivatives Derivatives, Fair Value [Line Items] Unrealized gain (loss) on derivative financial instruments, net of tax Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Taxes Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses. SPECIAL (GAINS) AND CHARGES SPECIAL (GAINS) AND CHARGES [Abstract] No definition available. Adjustment to Compensation: Adjustment to Compensation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Class of Stock [Domain] Class of Stock [Domain] Global Water Water Services [Member] Represents a reportable segment, which serves the global water treatment and process chemical needs of the industrial, institutional, and municipal markets. Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Thirty year 2017 senior notes Thirty Year 2017 Senior Notes [Member] Represents the thirty year 2017 senior notes that mature in 2047. Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Pension and postretirement plan contributions Payment for Pension and Other Postretirement Benefits Hedging Designation [Axis] Hedging Designation [Axis] Foreign currency forward contracts Foreign currency forward contracts Foreign Exchange Forward [Member] Capitalized software Capitalized Cost, Software to be Sold, Leased, or Marketed, before Accumulated Amortization Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Long-term debt Total long-term debt Long-Term Debt and Lease Obligation CAD Canada, Dollars Name Measure Name INCOME TAXES Income Tax Disclosure [Text Block] Other activity Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Five Year 2022 senior notes Five Year 2022 Senior Notes [Member] This member stands for Five Year 2022 Senior Notes. Other, net Other Noncash Income (Expense) Components of the company's debt obligations Debt instrument Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Total consideration transferred to sellers, net of cash acquired Business Combination, Consideration Transferred Retirement Plan Type [Domain] Retirement Plan Type [Domain] Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Intangible Asset, Indefinite-Lived, Class [Axis] Intangible Asset, Indefinite-Lived, Class [Axis] Three Year Fixed Rate Notes 4.60% Effective Rate 4.61% Three Year 2026 senior notes Three Year Senior Notes Fixed Rate Notes 4.60% Effective Rate 4.61% [Member] Three Year 2026 Senior Notes Special charges to date, after tax Special Charges To Date, After Tax The amount of non-restructuring special charges incurred to date. Goodwill, impairment loss Goodwill, Impairment Loss Revision of Prior Period [Axis] Revision of Prior Period [Axis] Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Retirement Plan Sponsor Location [Axis] Retirement Plan Sponsor Location [Axis] European commercial paper European Commercial Paper [Member] Represents the entity's European commercial paper program. Increase in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect, Continuing Operation Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Operating Lease, Liability, Current, Statement of Financial Position Flag Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Company Selected Measure Amount Company Selected Measure Amount Schedule of reportable segment information Segment Reporting, Reconciliation of Profit (Loss) by Segment to Consolidated [Table Text Block] Operating lease liabilities Operating Lease Liability Noncurrent, Excluded From Long-term Debt Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent and excluded from long-term debt obligations. Derivatives not designated as hedging instruments Not Designated as Hedging Instrument [Member] Retirement Plan Sponsor Location [Domain] Retirement Plan Sponsor Location [Domain] Stock, Class of Stock [Table] Stock, Class of Stock [Table] Net income including noncontrolling interest Net income including noncontrolling interest Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Current assets Assets, Current [Abstract] Net value of derivatives Carrying amount of the hedged liabilities Derivative Liability Non-PEO NEO Non-PEO NEO [Member] Senior Notes Seven year 2008 senior notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Provision for income taxes Income Tax Expense (Benefit) Latin America Latin America [Member] Fair Value Hedges Fair Value Hedging [Member] Cost of Sales COS Cost of Product and Service Sold Cost of Product and Service Sold Activity in the allowance for doubtful accounts SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] Technology Technology-Based Intangible Assets [Member] Award Timing Method Award Timing Method [Text Block] Thirty year 2011 senior notes Thirty Year 2011 Senior Notes [Member] Represents the thirty year 2011 senior notes. Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Total special (gains) and charges Special Gains and Charges Special gains and charges includes items that are unusual in nature, significant in amount and important to an understanding of underlying business performance. Recognition of net actuarial loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) NEW ACCOUNTING PRONOUNCEMENTS Accounting Standards Update and Change in Accounting Principle [Text Block] Net income attributable to Ecolab Net income attributable to Ecolab Net Income (Loss) Attributable to Parent Net tax expense (benefit) related to discrete tax item Income Tax Expense (Benefit), Discrete Impact of discrete tax items recognized during the period. Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Location, Statement of Financial Position, Balance [Axis] Location, Statement of Financial Position, Balance [Axis] Statement [Table] Statement [Table] Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member] Other Restructuring Plan ImmaterialRestructuringPlan [Member] Information pertaining to an immaterial restructuring plan. Restatement Determination Date: Restatement Determination Date [Axis] Exercise of employee stock options Proceeds from Stock Options Exercised Interest rate swap agreements Interest Rate Derivative Liabilities, at Fair Value Interest income Investment Income, Interest Schedule of contract asset and liability Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Change in contract liability Change in Contract with Customer, Liability [Abstract] Euronotes Euro Notes [Member] Euro Notes [Member] Principal year Long-Term Debt, Term Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Nonqualified Plan [Member]