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entroCIM Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired 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 Finite-Lived Intangible Asset, Expected Amortization, Year Two Finite-Lived Intangible Asset, Expected Amortization, Year Two Defined Benefit Plan, Service Cost Defined Benefit Plan, Service Cost Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Accrued payroll and benefit costs Employee-related Liabilities, Current Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Exercised Stockholders' Equity Note Disclosure Equity [Text Block] Fair value of cash consideration Payment to Acquire Business, Fair Value of Cash Consideration Payment to Acquire Business, Fair Value of Cash Consideration Net income attributable to WESCO International, Inc. 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Fiscal Year End Date Subsequent Event Type [Domain] Subsequent Event Type [Domain] Expected life (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] CSS CSS [Member] CSS Retirement Plan Type [Axis] Retirement Plan Type [Axis] Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Statement [Table] Statement [Table] Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Financing Activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value EES EES [Member] EES Fair value of net assets acquired, including goodwill and intangible assets Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill Variable Rate [Domain] Variable Rate [Domain] Investment Tax Credit Investment Tax Credit Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Amendment Flag Amendment Flag Gross Profit [Abstract] Gross Profit [Abstract] Treasury Stock, Value Treasury Stock, Common, Value Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Finite-Lived Intangible Asset, Expected Amortization, after Year Five Finite-Lived Intangible Asset, Expected Amortization, after Year Five Share-Based Payment Arrangement, Option, Activity Share-Based Payment Arrangement, Option, Activity [Table Text Block] Dividends Payable [Table] Dividends Payable [Table] Weighted average common shares outstanding used in computing basic earnings per share (in shares) Weighted Average Number of Shares Outstanding, Basic Cost of goods sold Cost of Product and Service Sold Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Subsequent Events [Abstract] Subsequent Events [Abstract] Segment Reporting [Abstract] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Risk free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Entity Tax Identification Number Entity Tax Identification Number Scenario [Domain] Scenario [Domain] Debt Instrument, Unamortized Discount Debt Instrument, Unamortized Discount Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares, issued (in shares) Common Stock, Shares, Issued Common Stock, Shares, Issued Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Goodwill and Intangible Assets Disclosure Goodwill and Intangible Assets Disclosure [Text Block] Shipping and Handling [Member] Shipping and Handling [Member] Schedule of Goodwill [Table Text Block] Schedule of Goodwill [Table Text Block] SUBSEQUENT EVENTS Subsequent Events [Text Block] Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Security Exchange Name Security Exchange Name Liabilities Liabilities Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Dividends, Preferred Stock Dividends, Preferred Stock Dividends, Preferred Stock Industrial Software Solutions Industrial Software Solutions [Member] Industrial Software Solutions Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-Lived Intangible Assets, Major Class Name [Domain] Operating Expenses [Abstract] Operating Expenses [Abstract] Other Liabilities, Current Other Liabilities, Current Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture Statement [Line Items] Statement [Line Items] Consolidation Items [Axis] Consolidation Items [Axis] Variable Rate [Axis] Variable Rate [Axis] 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 Subsequent Event [Line Items] Subsequent Event [Line Items] Common Stock Common Stock [Member] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code 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 Chief Executive Officer [Member]