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Aggregate Intrinsic Value, Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Schedule of Goodwill [Table] Goodwill [Table] Long-Lived Asset, Disposed of Other than by Sale, Gain (Loss) from Disposal Long-Lived Asset, Disposed of Other than by Sale, Gain (Loss) from Disposal Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Subsequent Event [Line Items] Subsequent Event [Line Items] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Proceeds from issuance of long-term debt Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number 6.00% Senior Notes due 2025 6.00% Senior Notes due 2025 [Member] 6.00% Senior Notes due 2025 CANADA CANADA Consolidation Items [Axis] Consolidation Items [Axis] Entity Registrant Name Entity Registrant Name Entity Address, Postal Zip Code Entity Address, Postal Zip Code Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Commitments and Contingencies Commitments and Contingencies Intangible Asset, Finite-Lived, before Accumulated Amortization Intangible Asset, Finite-Lived, before Accumulated Amortization Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four Income Tax Contingency [Table] Income Tax Contingency [Table] O2024Q1Dividends O2024Q1Dividends [Member] O2024Q1Dividends Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Weighted Average Remaining Contractual Term, Exercisable (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term Inventories, net Inventory, Net Award Type [Domain] Award Type [Domain] Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Supplemental Cash Flow Information [Abstract] Supplemental Cash Flow Information [Abstract] Expected life (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense) Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense) Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, Amortization Expense Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, Amortization Expense Geographical [Axis] Geographical [Axis] Income Tax Paid, before Refund Received Income Tax Paid, before Refund Received Segment Reporting, Other Segment Item, Amount Segment Reporting, Other Segment Item, Amount Entity Tax Identification Number Entity Tax Identification Number 7.250% Senior Notes due 2028 7.250% Senior Notes due 2028 [Member] 7.250% Senior Notes due 2028 Weighted Average Exercise Price, Exercisable (in dollars per share) Share-Based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price Finite-Lived Intangible Asset, Expected Amortization, Total Finite-Lived Intangible Asset, Expected Amortization, Total Finite-Lived Intangible Asset, Expected Amortization, Total Treasury Stock, Value, Acquired, Cost Method Treasury Stock, Value, Acquired, Cost Method Treasury Stock, Value, Acquired, Cost Method Weighted Average Exercise Price, Exercises in Period (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Preferred Stock Dividends, Income Statement Impact Preferred Stock Dividends, Income Statement Impact Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Tax Year 2024 Tax Year 2024 [Member] Schedule of Finite-Lived Intangible Assets [Table] Intangible Asset, Finite-Lived [Table] Accounts payable Increase (Decrease) in Accounts Payable Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Debt Instrument [Axis] Debt Instrument [Axis] Subsequent Event [Table] Subsequent Event [Table] Business Combination, Reason for Business Combination Business Combination, Reason for Business Combination Stock-based compensation expense Share-Based Payment Arrangement, Noncash Expense Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Tax Period [Axis] Tax Period [Axis] entroCIM entroCIM [Member] entroCIM Schedule of Debt Schedule of Debt [Table Text Block] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Basic (in dollars per share) Earnings Per Share, Basic Deferred Revenue Deferred Revenue Payments for Repurchase of Common Stock Payments for Repurchase of Common Stock Assets, Current Assets, Current Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Total long-term debt Long-Term Debt, Excluding Current Maturities Award Type [Axis] Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Award Type and Plan Name [Axis] Award Type [Axis] Accounts Receivable, after Allowance for Credit Loss, Current Accounts Receivable, after Allowance for Credit Loss, Current Retained earnings Retained Earnings (Accumulated Deficit) Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] Fair value of cash consideration Payment to Acquire Business, Fair Value of Cash Consideration Payment to Acquire Business, Fair Value of Cash Consideration Pension Plan [Member] Pension Plan [Member] Common Stock Common Stock [Member] WESCO expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Cover page. Cover [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Non-US [Member] Non-US [Member] Redemption Premium Redemption Premium APIC, Share-based Payment Arrangement, Recognition and Exercise APIC, Share-Based Payment Arrangement, Recognition and Exercise Foreign Line of Credit Foreign Line of Credit [Member] Goodwill, Foreign Currency Translation, Gain (Loss) Goodwill, Foreign Currency Translation, Gain (Loss) Other Nonoperating Gains (Losses) Other Nonoperating Gains (Losses) Asset Acquisition [Line Items] Asset Acquisition [Line Items] Liabilities and Equity Liabilities and Equity Liabilities and Equity O2025Q3Dividends O2025Q3Dividends [Member] O2025Q3Dividends Share-based Payment Arrangement, Option Share-Based Payment Arrangement, Option [Member] Dividends Payable, Date to be Paid Dividends Payable, Date to be Paid Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Noncontrolling interest Stockholders' Equity Attributable to Noncontrolling Interest Equity, Attributable to Noncontrolling Interest Segments [Axis] Segments [Axis] Other current and noncurrent liabilities Increase (Decrease) in Other Operating Liabilities Income Tax Authority [Domain] Income Tax Jurisdiction [Domain] Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three CSS CSS [Member] CSS Aggregate Intrinsic Value, Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] EES EES [Member] EES Derivatives and Fair Value Derivatives and Fair Value [Text Block] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding Preferred Stock, Value, Issued Share Repurchase Program [Axis] Share Repurchase Program [Axis] Dividends Payable [Line Items] Dividends Payable [Line Items] Dividends Payable [Table] Dividends Payable [Table] Class of Stock [Domain] Class of Stock [Domain] Interest Paid, Excluding Capitalized Interest, Operating Activity Interest Paid, Excluding Capitalized Interest, Operating Activity Capital expenditures Payments to Acquire Productive Assets Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Income Tax Authority [Axis] Income Tax Jurisdiction [Axis] Deferred Revenue, Revenue Recognized Deferred Revenue, Revenue Recognized INCOME TAXES Income Tax Disclosure [Text Block] Accounts payable Accounts Payable, Current Debt Instrument [Line Items] Debt Instrument [Line Items] Total purchase consideration Business Combination, Consideration Transferred Retirement Plan Type [Domain] Retirement Plan Type [Domain] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Indefinite-lived Intangible Assets [Axis] Intangible Asset, Indefinite-Lived, Class [Axis] Dividends [Axis] Dividends [Axis] Restatement [Axis] Revision of Prior Period [Axis] Dividends Payable, Date Declared Dividends Payable, Date Declared Retirement Plan Sponsor Location [Axis] Retirement Plan Sponsor Location [Axis] Tax Period [Domain] Tax Period [Domain] Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number Retirement Plan Sponsor Location [Domain] Retirement Plan Sponsor Location [Domain] Preferred Stock, Redemption Amount Preferred Stock, Redemption Amount Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Senior Notes [Member] Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Vested in Period, Weighted Average Fair Value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Provision for income taxes Income Tax Expense (Benefit) Cost of goods sold Cost of Product and Service Sold Technology-Based Intangible Assets Technology-Based Intangible Assets [Member] Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forecast [Member] Forecast [Member] Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount Loss Contingency, Accrual, Current Loss Contingency, Accrual, Current New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Accounting Standards Update and Change in Accounting Principle [Text Block] Industrial Software Solutions Industrial Software Solutions [Member] Industrial Software Solutions Net income attributable to WESCO International, Inc. Net Income (Loss) Attributable to Parent Net income (loss) attributable to WESCO International, Inc. Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Share-based Payment Arrangement, Option and Stock Appreciation Rights, Activity [Table Text Block] Share-Based Payment Arrangement, Option and Stock Appreciation Rights, Activity [Table Text Block] Statement [Table] Statement [Table] Fair value adjustment to the Anixter Notes Debt Instrument, Unamortized Premium Percentage of principal amount of Senior Notes accelerated under default Percentage of principal amount of Senior Notes accelerated under default Percentage of principal amount of Senior Notes accelerated under default Payments for (Proceeds from) Productive Assets Payments for (Proceeds from) Productive Assets Business Combination, Effective Date of Acquisition Business Combination, Effective Date of Acquisition Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Forfeitures Chief Executive Officer [Member]