0000929008-24-000013 | 10-Q | XBRL Viewer

CONSOLIDATED BALANCE SHEETS (parenthetical items) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Accounts Receivable, Allowance for Credit Loss, Current	$ 57.0	$ 55.9
Accumulated depreciation	505.8	502.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	65.5	43.0
Deferred Income Tax Assets, Net	39.5	42.3
Asset, Held-for-Sale, Not Part of Disposal Group, Current		0.0
Asset, Held-for-Sale, Not Part of Disposal Group, Other		0.0
Total liabilities held for sale	71.8
Disposal Group, Including Discontinued Operation, Other Liabilities		0.0
Total current assets held for sale	243.6
Disposal Group, Including Discontinued Operation, Other Assets	65.6
Total current liabilities held for sale	68.7	$ 0.0
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	$ 3.1

EARNINGS PER SHARE

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

EARNINGS PER SHARE

Basic earnings per share is computed by dividing net income attributable to common stockholders by the weighted-average number of common shares outstanding during the periods. Diluted earnings per share is computed by dividing net income attributable to common stockholders by the weighted-average common shares and common share equivalents outstanding during the periods. The dilutive effect of common share equivalents is considered in the diluted earnings per share computation using the treasury stock method, which includes consideration of equity awards.

The following table sets forth the computation of basic and diluted earnings per share for the periods presented:


	Three Months Ended
	March 31
(In millions, except per share data)		2024		2023
Net income attributable to WESCO International, Inc.		$	115.8	$	197.1
Less: Preferred stock dividends		14.4		14.4
Net income attributable to common stockholders		$	101.4	$	182.7
Weighted-average common shares outstanding used in computing basic earnings per share		50.9		51.0
Common shares issuable upon exercise of dilutive equity awards		1.0		1.5
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share		51.9		52.5
Earnings per share attributable to common stockholders
Basic		$	1.99	$	3.58
Diluted		$	1.95	$	3.48

The computation of diluted earnings per share attributable to common stockholders excludes stock-based awards that would have had an antidilutive effect on earnings per share. For the three months ended March 31, 2024 and 2023, there were approximately 0.2 million and 0.4 million antidilutive shares, respectively.

INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
INCOME TAXES (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Income Tax Contingency [Line Items]
Effective tax rate	21.00%	18.30%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	$ 7.7	$ 21.2
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	530.00%	880.00%

INCOME TAXES	3 Months Ended
INCOME TAXES	Mar. 31, 2024
Income Tax Disclosure [Abstract]
INCOME TAXES	The effective tax rate for the three months ended March 31, 2024 and 2023 was 21.0% and 18.3%, respectively. For the three months ended March 31, 2024 and 2023, the effective tax rate reflects discrete income tax benefits of $7.7 million and $21.2 million, respectively, resulting from the exercise and vesting of stock-based awards. These discrete income tax benefits reduced the estimated annual effective tax rate in such periods by approximately 5.3 and 8.8 percentage points, respectively. The effective tax rate, excluding discrete income tax benefits, differs from the federal statutory income tax rate due primarily to state income taxes, nondeductible expenses, and the tax impact of international operations. There have been no material adjustments to liabilities for uncertain tax positions since December 31, 2023.

- Definition

The entire disclosure for income tax.

+ References

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+ Details

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Equity [Abstract]
Stock Repurchase Program, Authorized Amount	$ 1,000.0
Common Stock, Dividends, Per Share, Declared	$ 0.413	$ 0.375
Dividends, Common Stock	$ 20.9	$ 19.2
Treasury Stock, Value, Acquired, Cost Method	50.5
Dividends, Preferred Stock	$ 14.4	$ 14.4

EMPLOYEE BENEFIT PLANS - Components of Net Periodic Penson Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.5	$ 1.2
Interest cost	4.3	5.4
Expected return on plan assets	(3.8)	(5.4)
Recognized actuarial gain	(0.1)	(0.3)
Settlement	5.5	0.0
Net periodic pension cost	6.4	0.9
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0
Interest cost	1.0	2.6
Expected return on plan assets	(0.3)	(2.4)
Recognized actuarial gain	0.0	0.0
Settlement	5.5	0.0
Net periodic pension cost	6.2	0.2
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	1.2
Interest cost	3.3	2.8
Expected return on plan assets	(3.5)	(3.0)
Recognized actuarial gain	(0.1)	(0.3)
Settlement	0.0	0.0
Net periodic pension cost	$ 0.2	$ 0.7

INCOME TAXES Income Tax Rates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	21.00%	18.30%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	530.00%	880.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	$ 7.7	$ 21.2

STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2024

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

During the three months ended March 31, 2024 and 2023, Wesco granted the following stock options, restricted stock units, and performance-based awards at the following weighted-average fair values:


	Three Months Ended
		March 31, 2024		March 31, 2023
Stock options granted		85,425		75,182
Weighted-average fair value		$	72.05	$	76.77

Restricted stock units granted		202,299		170,569
Weighted-average fair value		$	152.10	$	171.03

Performance-based awards granted(1)		192,995		208,371
Weighted-average fair value(1)		$	108.72	$	85.94

(1) As described further below, the three months ended March 31, 2024 includes performance-based awards granted in February 2021 for which actual achievement levels were certified in February 2024, as well as performance-based awards granted during the three months ended March 31, 2024.

Share-based Payment Arrangement, Option and Stock Appreciation Rights, Activity [Table Text Block]

The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2023	818,284	$	59.55
Granted	—	—
Exercised	(26,413)	63.82
Forfeited	(244)	85.35
Outstanding at March 31, 2024	791,627	$	59.40	4.8	$	88.6
Exercisable at March 31, 2024	790,495	$	59.37	4.8	$	88.5

For the three months ended March 31, 2024, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $2.8 million.

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

The following table sets forth a summary of restricted stock units and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	407,613	$	127.49
Granted	202,299	152.10
Vested	(184,135)	116.57
Forfeited	(17,621)	138.41
Unvested at March 31, 2024	408,156	$	144.03

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

The following table sets forth a summary of performance-based awards and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	254,859	$	115.15
Granted(1)	192,995	108.72
Vested	(223,042)	77.08
Forfeited	(4,226)	159.15
Unvested at March 31, 2024	220,586	$	147.18

(1) Includes 80,951 performance-based awards granted in February 2024 with a fair value of $152.07 and three-year performance period ending December 31, 2026, and 111,521 of additional performance-based awards related to awards originally granted in February 2021 with a fair value of $77.08 and three-year performance period ended December 31, 2023 for which actual achievement levels were certified in February 2024.

Share-Based Payment Arrangement, Option, Activity

The following table sets forth a summary of stock options and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2023	163,082	$	144.51
Granted	85,425	152.07
Exercised	(2,326)	122.09
Forfeited	(4,327)	155.67
Outstanding at March 31, 2024	241,854	$	147.20	8.9	$	5.9
Exercisable at March 31, 2024	77,608	$	136.81	8.2	$	2.7

For the three months ended March 31, 2024, the aggregate intrinsic value of stock options exercised during such period was not material.

Stock Appreciation Rights (SARs) [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The fair values of stock options, as disclosed in the table above, were estimated using the following weighted-average assumptions in the respective periods:


	Three Months Ended
		March 31, 2024		March 31, 2023
Risk free interest rate		4.2	%	4.1	%
Expected life (in years)		5		5
Expected volatility		55	%	50	%
Expected dividend yield		1.09	%	0.88	%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended
Segment Reporting (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Segment Reporting [Abstract]
Revenues	$ 5,350.0	$ 5,521.9
Operating Income (Loss)	263.0	346.4
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,350.0	5,521.9
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating Income (Loss)	263.0	346.4
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	15,539.0		$ 15,060.9
Other Nonoperating Income (Expense)	(21.6)	(10.1)
EES
Segment Reporting [Abstract]
Adjusted EBITDA	$ 165.8	$ 183.0
Adjusted EBITDA Margin %	7.90%	8.60%
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 2,099.0	$ 2,135.1
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	4,620.5		4,553.6
Depreciation, Depletion and Amortization	11.2	9.9
Other Nonoperating Income (Expense)	5.7	0.5
CSS
Segment Reporting [Abstract]
Adjusted EBITDA	$ 127.2	$ 155.5
Adjusted EBITDA Margin %	7.60%	9.00%
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,670.1	$ 1,732.0
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	5,502.9		5,626.6
Depreciation, Depletion and Amortization	18.0	18.0
Other Nonoperating Income (Expense)	18.8	0.8
UBS
Segment Reporting [Abstract]
Adjusted EBITDA	$ 169.4	$ 187.7
Adjusted EBITDA Margin %	10.70%	11.30%
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,580.9	$ 1,654.8
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	3,992.7		3,908.5
Depreciation, Depletion and Amortization	7.0	6.0
Other Nonoperating Income (Expense)	0.8	$ 0.6
Corporate Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 1,422.9		$ 972.2

REVENUE (Details) - USD ($) $ in Millions	3 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 150.3		$ 111.9
Revenue from Contract with Customer, Excluding Assessed Tax	5,350.0	$ 5,521.9
Cost of goods sold	4,212.1	4,313.4
Contract with Customer, Refund Liability	37.4		$ 41.3
EES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,099.0	2,135.1
CSS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,670.1	1,732.0
UBS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,580.9	1,654.8
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	3,997.6	4,090.5
CANADA
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	718.5	759.4
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	633.9	672.0
Shipping and Handling [Member]
Disaggregation of Revenue [Line Items]
Cost of goods sold	$ 69.6	$ 76.9

Segment Reporting (Tables)

3 Months Ended

Mar. 31, 2024

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

The following tables set forth financial information by reportable segment for the periods presented:


(In millions)	Three Months Ended March 31, 2024
	EES		CSS		UBS		Total
Net sales	$	2,099.0	$	1,670.1	$	1,580.9	$	5,350.0

	Three Months Ended March 31, 2023
(In millions)	EES		CSS		UBS		Total
Net sales	$	2,135.1	$	1,732.0	$	1,654.8	$	5,521.9


(In millions)	Three Months Ended March 31, 2024
	EES			CSS			UBS
Adjusted EBITDA	$	165.8		$	127.2		$	169.4
Adjusted EBITDA Margin %	7.9		%	7.6		%	10.7		%

	Three Months Ended March 31, 2023
(In millions)	EES			CSS			UBS
Adjusted EBITDA	$	183.0		$	155.5		$	187.7
Adjusted EBITDA Margin %	8.6		%	9.0		%	11.3		%


(In millions)	Three Months Ended March 31, 2024
	EES		CSS		UBS
Depreciation and amortization	$	11.2	$	18.0	$	7.0
Other expense, net	5.7		18.8		0.8

	Three Months Ended March 31, 2023
(In millions)	EES		CSS		UBS
Depreciation and amortization	$	9.9	$	18.0	$	6.0
Other expense, net	0.5		0.8		0.6

The following table sets forth total assets by reportable segment for the periods presented:


	As of
	March 31, 2024
(In millions)	EES		CSS		UBS		Corporate(1)		Total
Total assets	$	4,620.5	$	5,502.9	$	3,992.7	$	1,422.9	$	15,539.0

	As of
	December 31, 2023
(In millions)	EES		CSS		UBS		Corporate(1)		Total
Total assets	$	4,553.6	$	5,626.6	$	3,908.5	$	972.2	$	15,060.9

(1) Total assets for Corporate primarily consist of cash and cash equivalents, deferred income taxes, property, buildings and equipment, capitalized cloud computing arrangement costs, operating lease assets, and pension as

ASSETS AND LIABILITIES HELD FOR SALE - Summary Current & Noncurrent Assets and Liabilities Classified as Held For Sale (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Discontinued Operations and Disposal Groups [Abstract]
Cash and cash equivalents	$ 1.4
Trade accounts receivable, net	214.9
Other accounts receivable	3.5
Inventories	21.4
Prepaid expenses and other current assets	2.4
Total current assets held for sale	243.6
Property, buildings and equipment, net	3.4
Operating lease assets	3.4
Goodwill	58.1
Other assets	0.7
Total assets held for sale	309.2
Accounts payable	67.8
Accrued payroll and benefit costs	0.4
Other current liabilities	0.5
Total current liabilities held for sale	68.7	$ 0.0
Operating lease liabilities	3.1
Total liabilities held for sale	$ 71.8

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	From time to time, a number of lawsuits and claims have been or may be asserted against the Company relating to the conduct of its business, including litigation relating to commercial, product and employment matters (including wage and hour). The outcome of any litigation cannot be predicted with certainty, and some lawsuits may be determined adversely to Wesco. However, management does not believe that the ultimate outcome of any such pending matters is likely to have a material adverse effect on Wesco’s financial condition or liquidity, although the resolution in any fiscal period of one or more of these matters may have a material adverse effect on Wesco’s results of operations for that period.

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	3 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Gross Profit [Abstract]
Revenues	$ 5,350.0	$ 5,521.9
Cost of goods sold	4,212.1	4,313.4
Operating Expenses [Abstract]
Selling, general and administrative expense	829.4	817.7
Depreciation and amortization	45.5	44.4
Income from operations	263.0	346.4
Interest Income (Expense), Nonoperating, Net	94.4	95.0
Other Nonoperating Income (Expense)	21.6	10.1
Income before income taxes	147.0	241.3
Provision for income taxes	30.9	44.1
Net income	116.1	197.2
Net (loss) income attributable to noncontrolling interest	0.3	0.1
Net income attributable to WESCO International, Inc.	115.8	197.1
Preferred Stock Dividends, Income Statement Impact	14.4	14.4
Net Income (Loss) Available to Common Stockholders, Basic	$ 101.4	$ 182.7
Basic (in dollars per share)	$ 1.99	$ 3.58
Diluted (in dollars per share)	$ 1.95	$ 3.48
Comprehensive Income:
Foreign currency translation adjustment	$ (71.6)	$ 17.0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	1.9	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(69.7)	17.0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	46.4	214.2
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0.3	0.1
Dividends, Preferred Stock	14.4	14.4
Comprehensive income attributable to WESCO International, Inc.	$ 31.7	$ 199.7

ASSETS AND LIABILITIES HELD FOR SALE - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Discontinued Operations and Disposal Groups [Abstract]
Income before income taxes	$ 11.5	$ 11.4

SCHEDULE OF DEBT (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Finance lease obligations	$ 42.3	$ 31.4
Total debt	5,255.0	5,359.0
Fair value adjustment to the Anixter Notes	0.1	0.1
Unamortized debt issuance costs	(60.2)	(37.4)
Short-term debt and current portion of long-term debt	(11.1)	(8.6)
Total long-term debt	5,183.8	5,313.1
Foreign Line of Credit
Debt Instrument [Line Items]
Long-term Debt	0.8	1.0
Accounts Receivable Securitization Facility
Debt Instrument [Line Items]
Long-term Debt	638.0	1,550.0
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Debt	0.0	953.0
6.00% Senior Notes due 2025
Debt Instrument [Line Items]
Long-term Debt	4.2	4.2
7.125% Senior Notes due 2025
Debt Instrument [Line Items]
Long-term Debt	1,500.0	1,500.0
7.250% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term Debt	1,319.7	1,319.4
Debt Instrument, Unamortized Discount	5.3	5.6
6.375% Senior Notes due 2029
Debt Instrument [Line Items]
Long-term Debt	900.0	0.0
6.625% Senior Notes due 2032
Debt Instrument [Line Items]
Long-term Debt	$ 850.0	$ 0.0

DEBT (Notes)

3 Months Ended

Mar. 31, 2024

Debt Instrument [Line Items]

Debt Disclosure [Text Block]

10. DEBT

The following table sets forth Wesco's outstanding indebtedness:


	As of
	March 31, 2024		December 31, 2023
	(In millions)
International lines of credit	$	0.8	$	1.0
Accounts Receivable Securitization Facility	638.0		1,550.0
Revolving Credit Facility	—		953.0
6.00% Anixter Senior Notes due 2025	4.2		4.2
7.125% Senior Notes due 2025	1,500.0		1,500.0
7.250% Senior Notes due 2028, less debt discount of $5.3 and $5.6 in 2024 and 2023, respectively	1,319.7		1,319.4
6.375% Senior Notes due 2029	900.0		—
6.625% Senior Notes due 2032	850.0		—
Finance lease obligations	42.3		31.4
Total debt	5,255.0		5,359.0
Plus: Fair value adjustments to the Anixter Senior Notes	0.1		0.1
Less: Unamortized debt issuance costs	(60.2)		(37.4)
Less: Short-term debt and current portion of long-term debt	(11.1)		(8.6)
Total long-term debt	$	5,183.8	$	5,313.1

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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- Definition

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+ Details

REVENUE Variable Consideration (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue, Methods, Inputs, and Assumptions Used [Abstract]
Revenue, Variable Consideration Constraint Increase (Decrease)	$ 110.8	$ 96.5

ORGANIZATION	3 Months Ended
ORGANIZATION	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION	WESCO International, Inc. (“Wesco International”) and its subsidiaries (collectively, “Wesco” or the “Company”), headquartered in Pittsburgh, Pennsylvania, is a leading provider of business-to-business distribution, logistics services and supply chain solutions. The Company has operating segments comprising three strategic business units consisting of Electrical & Electronic Solutions (“EES”), Communications & Security Solutions (“CSS”) and Utility & Broadband Solutions (“UBS”).

SUMMARY OF PERFORMANCE-BASED AWARDS (Details) - Performance Shares [Member] - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	220,586		254,859
Granted (in shares)	192,995	208,371
Vested (in shares)	(223,042)
Forfeited (in shares)	(4,226)
Unvested, Weighted Average Fair Value (in dollars per share)	$ 147.18		$ 115.15
Granted, Weighted Average Fair Value (in dollars per share)	108.72	$ 85.94
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$ 159.15

Equity

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Stockholders' Equity Note Disclosure

Share Repurchases

On May 31, 2022, the Company’s Board of Directors adopted a resolution authorizing the repurchase of up to $1 billion of the Company’s common stock and Series A Preferred Stock. The share repurchase authorization has no expiration date and may be modified, suspended, or terminated at any time without prior notice.

During the three months ended March 31, 2024, the Company entered into spot repurchase transactions through a broker to purchase 343,147 shares of its common stock in the open market for cash totaling $50.5 million, including excise taxes. Wesco funded the repurchases with available cash and borrowings under its Revolving Credit Facility. No shares of common stock were repurchased under the share repurchase authorization during the three months ended March 31, 2023.

Dividends

The Company’s dividends on common stock are declared at the discretion of the Board of Directors. The following table is a summary of cash dividends declared and paid on the Company’s common stock for the three months ended March 31, 2024:

Date Declared

Record Date

Payment Date

Amount per share

Dividend Payment

February 29, 2024

March 15, 2024

March 29, 2024

0.413

20.9

million

The following table is a summary of cash dividends declared and paid on the Company’s common stock for the three months ended March 31, 2023:

Date Declared

Record Date

Payment Date

Amount per share

Dividend Payment

March 3, 2023

March 15, 2023

March 31, 2023

0.375

19.2

million

During the three months ended March 31, 2024 and 2023, the Company's Board of Directors also declared and the Company paid quarterly cash dividends of $0.664 per depositary share relating to its Series A Preferred Stock totaling $14.4 million each quarter.

- Definition

The entire disclosure for equity.

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+ Details

DEBT (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of Debt

The following table sets forth Wesco's outstanding indebtedness:


	As of
	March 31, 2024		December 31, 2023
	(In millions)
International lines of credit	$	0.8	$	1.0
Accounts Receivable Securitization Facility	638.0		1,550.0
Revolving Credit Facility	—		953.0
6.00% Anixter Senior Notes due 2025	4.2		4.2
7.125% Senior Notes due 2025	1,500.0		1,500.0
7.250% Senior Notes due 2028, less debt discount of $5.3 and $5.6 in 2024 and 2023, respectively	1,319.7		1,319.4
6.375% Senior Notes due 2029	900.0		—
6.625% Senior Notes due 2032	850.0		—
Finance lease obligations	42.3		31.4
Total debt	5,255.0		5,359.0
Plus: Fair value adjustments to the Anixter Senior Notes	0.1		0.1
Less: Unamortized debt issuance costs	(60.2)		(37.4)
Less: Short-term debt and current portion of long-term debt	(11.1)		(8.6)
Total long-term debt	$	5,183.8	$	5,313.1

Segment Reporting

3 Months Ended

Mar. 31, 2024

Segment Reporting [Abstract]

Segment Reporting Disclosure

15. BUSINESS SEGMENTS

The Company has operating segments comprising three strategic business units consisting of EES, CSS and UBS. These operating segments are equivalent to the Company’s reportable segments. The Company’s chief operating decision maker evaluates the performance of its operating segments based on net sales, adjusted earnings before interest, taxes, depreciation and amortization (“EBITDA”), and adjusted EBITDA margin percentage.

The Company incurs corporate costs primarily related to treasury, tax, information technology, legal and other centralized functions. The Company also has various corporate assets. Segment assets may not include jointly used assets, but segment results include depreciation expense or other allocations related to those assets. Interest expense and other non-operating items are either not allocated to the segments or reviewed on a segment basis. Corporate expenses and assets not directly identifiable with a reportable segment are reported in the tables below to reconcile the reportable segments to the consolidated financial statements.

The following tables set forth financial information by reportable segment for the periods presented:


(In millions)	Three Months Ended March 31, 2024
	EES		CSS		UBS		Total
Net sales	$	2,099.0	$	1,670.1	$	1,580.9	$	5,350.0

	Three Months Ended March 31, 2023
(In millions)	EES		CSS		UBS		Total
Net sales	$	2,135.1	$	1,732.0	$	1,654.8	$	5,521.9


(In millions)	Three Months Ended March 31, 2024
	EES			CSS			UBS
Adjusted EBITDA	$	165.8		$	127.2		$	169.4
Adjusted EBITDA Margin %	7.9		%	7.6		%	10.7		%

	Three Months Ended March 31, 2023
(In millions)	EES			CSS			UBS
Adjusted EBITDA	$	183.0		$	155.5		$	187.7
Adjusted EBITDA Margin %	8.6		%	9.0		%	11.3		%


(In millions)	Three Months Ended March 31, 2024
	EES		CSS		UBS
Depreciation and amortization	$	11.2	$	18.0	$	7.0
Other expense, net	5.7		18.8		0.8

	Three Months Ended March 31, 2023
(In millions)	EES		CSS		UBS
Depreciation and amortization	$	9.9	$	18.0	$	6.0
Other expense, net	0.5		0.8		0.6

The following table sets forth total assets by reportable segment for the periods presented:


	As of
	March 31, 2024
(In millions)	EES		CSS		UBS		Corporate(1)		Total
Total assets	$	4,620.5	$	5,502.9	$	3,992.7	$	1,422.9	$	15,539.0

	As of
	December 31, 2023
(In millions)	EES		CSS		UBS		Corporate(1)		Total
Total assets	$	4,553.6	$	5,626.6	$	3,908.5	$	972.2	$	15,060.9

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

REVENUE (Notes)

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Revenue from Contract with Customer

3. REVENUE

Wesco distributes products and provides services to customers globally in various end markets within its business segments. The segments operate in the United States, Canada and various other countries.

The following tables disaggregate Wesco’s net sales by segment and geography for the periods presented:


	Three Months Ended
	March 31
(In millions)		2024		2023
Electrical & Electronic Solutions		$	2,099.0	$	2,135.1
Communications & Security Solutions		1,670.1		1,732.0
Utility & Broadband Solutions		1,580.9		1,654.8
Total by segment		$	5,350.0	$	5,521.9


	Three Months Ended
	March 31
(In millions)		2024		2023
United States		$	3,997.6	$	4,090.5
Canada		718.5		759.4
Other International(1)		633.9		672.0
Total by geography(2)		$	5,350.0	$	5,521.9

(1) No individual country's net sales are greater than 10% of total net sales.

(2) Wesco attributes revenues from external customers to individual countries on the basis of point of sale.

Due to the terms of certain contractual arrangements, Wesco bills or receives payment from its customers in advance of satisfying the respective performance obligation. Such advance billings or payments are recorded as deferred revenue and recognized as revenue when the performance obligation has been satisfied and control has transferred to the customer, which is generally upon shipment. Deferred revenue is usually recognized within a year or less from the date of the advance billing or payment. At March 31, 2024 and December 31, 2023, $150.3 million and $111.9 million, respectively, of deferred revenue was recorded as a component of other current liabilities in the Condensed Consolidated Balance Sheets. The Company recognized $42.8 million and $21.0 million of revenue during the three months ended March 31, 2024 and 2023, respectively, that was included in the deferred revenue balances as of December 31, 2023 and 2022, respectively.

The Company also has certain long-term contractual arrangements where revenue is recognized over time based on the cost-to-cost input method. As of March 31, 2024 and December 31, 2023, the Company had contract assets of $34.3 million and $35.4 million, respectively, resulting from contracts where the amount of revenue recognized exceeded the amount billed to the customer. Contract assets are recorded in the Condensed Consolidated Balance Sheets as a component of prepaid expenses and other current assets.

Wesco’s revenues are adjusted for variable consideration, which includes customer volume rebates, returns and discounts. Wesco measures variable consideration by estimating expected outcomes using analysis and inputs based upon historical data, as well as current and forecasted information. Variable consideration is reviewed by management on a monthly basis and revenue is adjusted accordingly. Variable consideration reduced revenue for the three months ended March 31, 2024 and 2023 by approximately $110.8 million and $96.5 million, respectively. As of March 31, 2024 and December 31, 2023, the Company's estimated product return obligation was $37.4 million and $41.3 million, respectively.

Billings to customers for shipping and handling are recognized in net sales. Wesco has elected to recognize shipping and handling costs as a fulfillment cost. Shipping and handling costs recorded as a component of selling, general and administrative expenses totaled $69.6 million and $76.9 million for the three months ended March 31, 2024 and 2023, respectively

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

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+ Details

EMPLOYEE BENEFIT PLANS (Notes)

3 Months Ended

Mar. 31, 2024

Retirement Benefits [Abstract]

EMPLOYEE BENEFIT PLANS

The following table sets forth the components of net periodic pension cost for the Company’s defined benefit plans:


	Three Months Ended March 31
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	0.5	$	1.2	$	0.5	$	1.2
Interest cost	1.0		2.6		3.3		2.8		4.3		5.4
Expected return on plan assets	(0.3)		(2.4)		(3.5)		(3.0)		(3.8)		(5.4)
Recognized actuarial gain(3)	—		—		(0.1)		(0.3)		(0.1)		(0.3)
Settlement	5.5		—		—		—		5.5		—
Net periodic pension cost	$	6.2	$	0.2	$	0.2	$	0.7	$	6.4	$	0.9

(1) Defined as the Anixter Inc. Pension Plan, which was settled during the first quarter of 2024, as described below.

(2) Defined as the EECOL Electric ULC Retirement Plan, the EECOL Electric ULC Supplemental Executive Retirement Plan, the Pension Plan for Employees of Anixter Canada Inc., and various defined benefit pension plans covering employees of foreign subsidiaries in Europe.

(3) For the three months ended March 31, 2024 and 2023, no material amounts were reclassified from accumulated other comprehensive income into net income.

Service cost is reported as a component of selling, general and administrative expenses. The other components of net periodic pension cost (benefit) totaling net costs of $5.9 million for the three months ended March 31, 2024, and net benefits $0.3 million for the three months ended March 31, 2023, are presented as components of other expense, net.

The Company expects to contribute approximately $7.0 million to its Foreign Plans in 2024. Approximately $2.4 million was contributed during the three months ended March 31, 2024. The Company did not make any contributions to its domestic qualified pension plan during the three months ended March 31, 2024 due to the plan’s settlement, as described below.

Anixter Inc. Pension Plan Settlement

On February 12, 2024, the remaining benefit obligation of the Anixter Inc. Pension Plan was settled through the purchase of single premium annuity contracts for total cash of $138.8 million. The purchase was funded entirely by the assets of the plan.

The final settlement of the Anixter Inc. Pension Plan triggered a remeasurement of the related plan benefit obligations and assets as of February 29, 2024. The net effect of the plan remeasurement was a reduction of $30.6 million to the net funded status of the plan, which represented an excess plan asset reversion, and was accounted for as a negative employer contribution. The assets related to the excess plan asset reversion are included in other current assets in the Condensed Consolidated Balance Sheet as of March 31, 2024. Additionally, the Company incurred excise taxes of $4.8 million resulting from the excess plan asset reversion, which are recorded as a component of selling, general and administrative expenses in the Condensed Consolidated Statement of Income during the three months ended March 31, 2024 and are included in other current liabilities in the Condensed Consolidated Balance Sheet as of March 31, 2024.

During the three months ended March 31, 2024, the Company recognized settlement costs of $5.5 million to recognize unrealized losses previously reported as a component of other comprehensive income (loss) related to the benefit obligation of the Anixter Inc. Pension Plan.

Other Employee Benefit Plans

Wesco sponsors defined contribution retirement savings plans for the majority of its employees in the U.S. and certain employees in Canada, which provide employer contributions.

Wesco incurred expenses of $18.8 million and $21.4 million for the three months ended March 31, 2024 and 2023, respectively, for its defined contribution plans.

Wesco Distribution sponsors a non-qualified deferred compensation plan (the “Wesco Deferred Compensation Plan”) that permits select employees to make pre-tax deferrals of salary and bonus. Employees have the option to transfer balances allocated to their accounts in the Wesco Deferred Compensation Plan into any of the available investment options. The Wesco Deferred Compensation Plan is an unfunded plan. As of March 31, 2024 and December 31, 2023, the Company’s obligation under the Wesco Deferred Compensation Plan was $29.8 million and $27.4 million, respectively, which is included in other noncurrent liabilities in the Condensed Consolidated Balance Sheets.

- Definition

The entire disclosure for retirement benefits.

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+ Details

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net income (loss) attributable to WESCO International, Inc.	$ 115.8	$ 197.1

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

EMPLOYEE BENEFIT PLANS - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	Feb. 12, 2024	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost		$ 18.8	$ 21.4
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year		7.0
Defined Benefit Plan, Plan Assets, Contributions by Employer		2.4
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	$ 138.8
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan		30.6
Excise and Sales Taxes		$ 4.8
Settlement		Other Nonoperating Income (Expense)
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Nonoperating Gains (Losses)		$ 5.9	$ (0.3)
WESCODeferredCompensationPlanMember
Defined Benefit Plan Disclosure [Line Items]
Deferred Compensation Liability, Classified, Noncurrent		$ 29.8		$ 27.4

GOODWILL (Notes)

3 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets Disclosure

The following table sets forth the changes in the carrying value of goodwill by reportable segment for the period presented:


	Three Months Ended
	March 31, 2024
	EES		CSS		UBS		Total
	(In millions)
Beginning balance, January 1	$	838.1	$	1,211.6	$	1,212.6	$	3,262.3
Foreign currency exchange rate changes	(12.2)		(3.8)		(5.7)		(21.7)
Reclassified as assets held for sale(1)	—		—		(58.1)		(58.1)
Ending balance, March 31	$	825.9	$	1,207.8	$	1,148.8	$	3,182.5

(1) Represents the amount of goodwill that is classified as held for sale related to the sale of the WIS business, as disclosed in Note 5, “Assets and Liabilities Held for Sale”.

The components of intangible assets are as follows:


		As of
		March 31, 2024						December 31, 2023
	Life (in years)	Gross Carrying Amount (1)		Accumulated Amortization (1)		Net Carrying Amount		Gross Carrying Amount (1)		Accumulated Amortization (1)		Net Carrying Amount
Intangible assets:		(In millions)
Trademarks	Indefinite	$	792.1	$	—	$	792.1	$	793.0	$	—	$	793.0
Customer relationships	10 - 20	1,511.3		(480.5)		1,030.8		1,519.9		(464.4)		1,055.5
Distribution agreements	15 and 19	29.2		(26.5)		2.7		29.2		(26.0)		3.2
Trademarks	5 and 12	15.5		(10.1)		5.4		15.5		(9.6)		5.9
		$	2,348.1	$	(517.1)	$	1,831.0	$	2,357.6	$	(500.0)	$	1,857.6

(1) Excludes the original cost and related accumulated amortization of fully-amortized intangible assets.

Amortization expense related to intangible assets totaled $21.9 million and $22.0 million for the three months ended March 31, 2024 and 2023, respectively.

The following table sets forth the remaining estimated amortization expense for intangible assets for the next five years and thereafter:


For the year ending December 31,	(In millions)
2024	$	64.0
2025	82.8
2026	77.5
2027	74.6
2028	72.9
Thereafter	667.1
Total	$	1,038.9

SCHEDULE OF SHARE-BASED COMPENSATION, STOCK OPTIONS AND STOCK APPRECIATION RIGHTS AWARD ACTIVITY (Details) - Stock Appreciation Rights (SARs) [Member] - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	791,627	818,284
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 59.40	$ 59.55
Granted (in shares)	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	(26,413)
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	$ 63.82
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	(244)
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	$ 85.35
Weighted Average Remaining Contractual Term, Outstanding (in years)	4 years 9 months 18 days
Aggregate Intrinsic Value, Outstanding	$ 88.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	790,495
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 59.37
Weighted Average Remaining Contractual Term, Exercisable (in years)	4 years 9 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 88.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 2.8

FAIR VALUE (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative, Notional Amount	$ 203.3	$ 168.4
Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value	4,635.5	2,880.3
Long-term Debt	$ 4,574.0	$ 2,823.7

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

REVENUE Revenue, Performance Obligation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Cost of goods sold	$ 4,212.1	$ 4,313.4

SUMMARY OF RESTRICTED STOCK UNITS (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based awards outstanding (in shares)	408,156		407,613
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 144.03		$ 127.49
Granted (in shares)	202,299	170,569
Granted, Weighted Average Fair Value (in dollars per share)	$ 152.10	$ 171.03
Vested (in shares)	(184,135)
Vested in Period, Weighted Average Fair Value (in dollars per share)	$ 116.57
Forfeited (in shares)	(17,621)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 138.41

EARNINGS PER SHARE (Tables)

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table sets forth the computation of basic and diluted earnings per share for the periods presented:


	Three Months Ended
	March 31
(In millions, except per share data)		2024		2023
Net income attributable to WESCO International, Inc.		$	115.8	$	197.1
Less: Preferred stock dividends		14.4		14.4
Net income attributable to common stockholders		$	101.4	$	182.7
Weighted-average common shares outstanding used in computing basic earnings per share		50.9		51.0
Common shares issuable upon exercise of dilutive equity awards		1.0		1.5
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share		51.9		52.5
Earnings per share attributable to common stockholders
Basic		$	1.99	$	3.58
Diluted		$	1.95	$	3.48

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024 shares
Trading Arrangements, by Individual
Name	Nelson Squires
Title	Executive Vice President and General Manager, Electrical & Electronic Solutions
Adoption Date	March 11, 2024
Termination Date	March 11, 2025
Aggregate Available	25,000

SUBSEQUENT EVENTS	3 Months Ended
SUBSEQUENT EVENTS	Mar. 31, 2024
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	16. SUBSEQUENT EVENTS On April 1, 2024, Wesco Distribution completed the sale of its WIS business for total consideration of approximately $338.3 million, adjusted from the base purchase price of $350.0 million for estimated net working capital, estimated closing cash, and estimated closing indebtedness. The Company expects to recognize a gain on sale in the range of $88.0 million to $108.0 million in the second quarter of 2024. Upon closing, Wesco Distribution entered into certain Transition Services Agreements (“TSAs”) under which Wesco Distribution agreed to provide transition services to the purchaser for approximately nine months. The Company does not expect the revenues associated with these TSAs to be material.

STOCK-BASED COMPENSATION (Notes)

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

STOCK-BASED COMPENSATION

Wesco’s stock-based compensation awards consist of stock options, stock-settled stock appreciation rights, restricted stock units and performance-based awards. Compensation cost for all stock-based awards is measured at fair value on the date of grant and compensation cost is recognized, net of estimated forfeitures, over the service period for awards expected to vest. The fair value of stock options and stock-settled stock appreciation rights is determined using the Black-Scholes model. The fair value of restricted stock units and performance-based awards with performance conditions is determined by the grant-date closing price of Wesco’s common stock. The forfeiture assumption is based on Wesco’s historical participant behavior that is reviewed on at least an annual basis. For stock options and stock-settled stock appreciation rights that are exercised, and for restricted stock units and performance-based awards that vest, shares are issued out of Wesco's outstanding common stock.

Stock options and stock-settled stock appreciation rights vest ratably over a three-year period and terminate on the tenth anniversary of the grant date unless terminated sooner under certain conditions. Restricted stock unit awards that were granted under the Company’s 1999 Long-Term Incentive Plan, as amended and restated, vest fully on the third anniversary of the date of grant. Restricted stock units awarded under the WESCO International, Inc. 2021 Omnibus Incentive Plan, which was adopted on May 27, 2021, vest ratably over a three-year period on each of the first, second and third anniversaries of the grant date. Vesting of performance-based awards is based on a three-year performance period, and the number of shares earned, if any, depends on the attainment of certain performance levels, as described below. Outstanding awards would vest upon the consummation of a change in control transaction with performance-based awards vesting at the greater of the target level or actual.

Performance-based awards are based on two equally-weighted performance measures: the three-year average growth rate of Wesco’s net income attributable to common stockholders and the three-year cumulative return on net assets. These awards are accounted for as awards with performance conditions; compensation cost is recognized over the performance period based upon Wesco’s determination of whether it is probable that the performance targets will be achieved.

During the three months ended March 31, 2024 and 2023, Wesco granted the following stock options, restricted stock units, and performance-based awards at the following weighted-average fair values:


	Three Months Ended
		March 31, 2024		March 31, 2023
Stock options granted		85,425		75,182
Weighted-average fair value		$	72.05	$	76.77

Restricted stock units granted		202,299		170,569
Weighted-average fair value		$	152.10	$	171.03

Performance-based awards granted(1)		192,995		208,371
Weighted-average fair value(1)		$	108.72	$	85.94

The fair values of stock options, as disclosed in the table above, were estimated using the following weighted-average assumptions in the respective periods:


	Three Months Ended
		March 31, 2024		March 31, 2023
Risk free interest rate		4.2	%	4.1	%
Expected life (in years)		5		5
Expected volatility		55	%	50	%
Expected dividend yield		1.09	%	0.88	%

The risk-free interest rate is based on the U.S. Treasury Daily Yield Curve rate as of the grant date. The expected life is based on historical exercise experience, the expected volatility is based on the volatility of the Company’s daily stock price over the expected life preceding the grant date of the award, and the expected dividend yield is based on the calculated yield on the Company’s common stock at date of grant using the current fiscal year projected dividend distribution rate.

The following table sets forth a summary of stock options and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2023	163,082	$	144.51
Granted	85,425	152.07
Exercised	(2,326)	122.09
Forfeited	(4,327)	155.67
Outstanding at March 31, 2024	241,854	$	147.20	8.9	$	5.9
Exercisable at March 31, 2024	77,608	$	136.81	8.2	$	2.7

For the three months ended March 31, 2024, the aggregate intrinsic value of stock options exercised during such period was not material.

The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2023	818,284	$	59.55
Granted	—	—
Exercised	(26,413)	63.82
Forfeited	(244)	85.35
Outstanding at March 31, 2024	791,627	$	59.40	4.8	$	88.6
Exercisable at March 31, 2024	790,495	$	59.37	4.8	$	88.5

For the three months ended March 31, 2024, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $2.8 million.

The following table sets forth a summary of restricted stock units and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	407,613	$	127.49
Granted	202,299	152.10
Vested	(184,135)	116.57
Forfeited	(17,621)	138.41
Unvested at March 31, 2024	408,156	$	144.03

The following table sets forth a summary of performance-based awards and related information for the three months ended March 31, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	254,859	$	115.15
Granted(1)	192,995	108.72
Vested	(223,042)	77.08
Forfeited	(4,226)	159.15
Unvested at March 31, 2024	220,586	$	147.18

Wesco recognized $10.1 million and $11.7 million of non-cash stock-based compensation expense for the three months ended March 31, 2024 and 2023, respectively, which is included in selling, general and administrative expenses for such periods. As of March 31, 2024, there was $84.1 million of total unrecognized compensation expense related to unvested stock-based compensation arrangements for all awards previously made, which is expected to be recognized as follows:

GOODWILL (Details) - USD ($) $ in Millions	3 Months Ended
GOODWILL (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Goodwill [Line Items]
Goodwill	$ 3,182.5		$ 3,262.3
Goodwill, Foreign Currency Translation Gain (Loss)	(21.7)
Goodwill, Transfers	(58.1)
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	2,348.1		2,357.6
Finite-Lived Intangible Assets, Accumulated Amortization	(517.1)		(500.0)
Finite-Lived Intangible Assets, Net	1,831.0		1,857.6
Finite-Lived Intangible Asset, Expected Amortization, Year One	64.0
Finite-Lived Intangible Asset, Expected Amortization, Year Two	82.8
Finite-Lived Intangible Asset, Expected Amortization, Year Three	77.5
Finite-Lived Intangible Asset, Expected Amortization, Year Four	74.6
Finite-Lived Intangible Asset, Expected Amortization, Year Five	72.9
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	667.1
Finite-Lived Intangible Asset, Expected Amortization, Total	1,038.9
Amortization of Intangible Assets	21.9	$ 22.0
Amortization of Intangible Assets	21.9	$ 22.0
Finite-Lived Intangible Asset, Expected Amortization, Year Three	77.5
Finite-Lived Intangible Asset, Expected Amortization, Year Four	74.6
Finite-Lived Intangible Asset, Expected Amortization, Year Five	72.9
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	667.1
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	15.5		15.5
Finite-Lived Intangible Assets, Accumulated Amortization	(10.1)		(9.6)
Finite-Lived Intangible Assets, Net	$ 5.4		5.9
Trademarks [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Trademarks [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	12 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,511.3		1,519.9
Finite-Lived Intangible Assets, Accumulated Amortization	(480.5)		(464.4)
Finite-Lived Intangible Assets, Net	$ 1,030.8		1,055.5
Customer Relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Customer Relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Distribution Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 29.2		29.2
Finite-Lived Intangible Assets, Accumulated Amortization	(26.5)		(26.0)
Finite-Lived Intangible Assets, Net	$ 2.7		3.2
Distribution Rights [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Distribution Rights [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	19 years
EES
Goodwill [Line Items]
Goodwill	$ 825.9		838.1
Goodwill, Foreign Currency Translation Gain (Loss)	(12.2)
Goodwill, Transfers	0.0
CSS
Goodwill [Line Items]
Goodwill	1,207.8		1,211.6
Goodwill, Foreign Currency Translation Gain (Loss)	(3.8)
Goodwill, Transfers	0.0
UBS
Goodwill [Line Items]
Goodwill	1,148.8		1,212.6
Goodwill, Foreign Currency Translation Gain (Loss)	(5.7)
Goodwill, Transfers	(58.1)
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 792.1		$ 793.0

ACCOUNTING POLICIES (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Supplier Finance Program, Obligation	$ 21.7		$ 32.6
Common Stock, Dividends, Per Share, Declared	$ 0.413	$ 0.375
Dividends, Preferred Stock	$ 14.4	$ 14.4
Dividends, Common Stock	(20.9)	$ (19.2)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	984.1		$ 524.1	$ 527.3
Cash and cash equivalents	$ 1.4

ACCOUNTING POLICIES	3 Months Ended
ACCOUNTING POLICIES	Mar. 31, 2024
Accounting Policies [Abstract]
ACCOUNTING POLICIES	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of Wesco have been prepared in accordance with Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). The unaudited condensed consolidated financial information should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in WESCO International, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the SEC on February 20, 2024. The Condensed Consolidated Balance Sheet at December 31, 2023 was derived from the audited Consolidated Financial Statements as of that date, but does not include all the disclosures required by accounting principles generally accepted in the United States of America. The unaudited Condensed Consolidated Balance Sheet as of March 31, 2024, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Stockholders’ Equity, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2024 and 2023, respectively, in the opinion of management, have been prepared on the same basis as the audited Consolidated Financial Statements and include all adjustments necessary for the fair statement of the results of the interim periods presented herein. All adjustments reflected in the unaudited condensed consolidated financial information are of a normal recurring nature unless indicated. The results for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year. Recently Adopted and Recently Issued Accounting Standards and Disclosure Rules In September 2022, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2022-04, Supplier Finance Programs (Subtopic 405-50): Disclosure of Supplier Finance Program Obligations, which requires that a buyer in a supplier finance program disclose sufficient information about the program to allow a user of financial statements to understand the program's nature, activity during the period, changes from period to period, and potential magnitude. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, except for the amendment on rollforward information, which is effective for fiscal years beginning after December 15, 2023. The Company adopted this ASU in the first quarter of 2023, except for the amendment on rollforward information, which the Company will begin disclosing in its Annual Report on Form 10-K for the year ending December 31, 2024. The adoption of this ASU resulted in additional disclosure of the Company's supplier finance program, as described below. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which enhances prior reportable segment disclosure requirements in part by requiring entities to disclose significant expenses related to their reportable segments. The amendments in this ASU are effective on a retrospective basis for annual periods beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires disaggregated information about a reporting entity's effective tax rate reconciliation as well as information on income taxes paid to enhance the transparency and decision usefulness of income tax disclosures. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 on a prospective basis. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In March 2024, the SEC issued final climate-related disclosure rules requiring disclosure of material climate-related risks, board and management governance of such risks, and material direct and indirect greenhouse gas emissions. The rules also require disclosure in the notes to the financial statements of the effects of severe weather events and other natural conditions. Disclosures will be made prospectively, with phased-in effective dates starting with fiscal years beginning on or after January 1, 2025. In April 2024, the SEC voluntarily stayed implementation of the climate-related disclosure rules, pending completion of judicial review of consolidated challenges to the rules by the Court of Appeals for the Eighth Circuit. Management is currently evaluating the impact that these rules could have on its consolidated financial statements and notes thereto. Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to be significant to Wesco’s financial position, results of operations or cash flows.

ASSETS AND LIABILITIES HELD FOR SALE

3 Months Ended

Mar. 31, 2024

Discontinued Operations and Disposal Groups [Abstract]

ASSETS AND LIABILITIES HELD FOR SALE

On February 22, 2024, Wesco Distribution entered into a definitive agreement to sell 100% of the equity interests of its Wesco Integrated Supply (“WIS”) business. The WIS business, located primarily in the U.S. and Canada, is part of the UBS segment and provides products and services to large industrial and commercial end-users to support their maintenance, repair, and operating spend. The sale was completed on April 1, 2024. Refer to Note 16, “Subsequent Events” for further information.

The following is a summary of the major categories of current and noncurrent assets and liabilities classified as held for sale in the Condensed Consolidated Balance Sheet:


	As of
	March 31, 2024
	(In millions)
Cash and cash equivalents	$	1.4
Trade accounts receivable, net	214.9
Other accounts receivable	3.5
Inventories	21.4
Prepaid expenses and other current assets	2.4
Total current assets held for sale	243.6
Property, buildings and equipment, net	3.4
Operating lease assets	3.4
Goodwill	58.1
Other assets	0.7
Total assets held for sale	$	309.2

Accounts payable	$	67.8
Accrued payroll and benefit costs	0.4
Other current liabilities	0.5
Total current liabilities held for sale	68.7
Operating lease liabilities	3.1
Total liabilities held for sale	$	71.8

Income before income taxes attributable to the WIS business was $11.5 million and $11.4 million for the three months ended March 31, 2024 and 2023, respectively.

The sale of the WIS business does not represent a strategic shift that will have a major effect on the Company’s operations and financial results, and therefore does not meet the criteria to be classified as discontinued operations.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY Statement - USD ($) $ in Millions	Total	Treasury Stock, Common [Member]	Common Class B [Member]	Common Stock [Member]	Series A Preferred Stock [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]	Retained Earnings [Member]	Additional Paid-in Capital [Member]	Treasury Stock, Common [Member]
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	68,535,704
Additional capital	$ 2,005.4
Retained Earnings (Accumulated Deficit)	3,795.0
Treasury Stock, Value	(969.1)
Stockholders' Equity Attributable to Noncontrolling Interest	(4.7)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (377.7)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					21,612
Treasury Stock, Common, Shares	22,115,653
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,449.6
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(12.6)			$ 0.0						$ 12.9
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.3
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	11.7
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(38.7)			$ 0.0				$ 24.5	$ 14.2
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				811,309						79,817
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(236,953)
Net Income (Loss) Attributable to Parent	197.1
Dividends, Preferred Stock	(14.4)
Stockholders' Equity, Other								(1.0)	0.1
Net Income (Loss) Attributable to Noncontrolling Interest	0.1						$ 0.1
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	16.1					$ 17.0
Dividends, Common Stock	(19.2)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,110,060
Additional capital	2,003.3
Retained Earnings (Accumulated Deficit)	3,933.0
Treasury Stock, Value	(982.0)
Stockholders' Equity Attributable to Noncontrolling Interest	(4.6)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (360.7)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					21,612
Treasury Stock, Common, Shares	22,195,470
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,589.7
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,278,677
Additional capital	2,037.1
Retained Earnings (Accumulated Deficit)	4,391.7
Treasury Stock, Value	(1,060.4)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.2)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(332.0)
Treasury stock, at cost; 23,069,535 and 22,720,986 shares in 2024 and 2023, respectively	$ (1,060.4)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					21,612
Treasury Stock, Common, Shares	22,720,986
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,031.9
Treasury Stock, Value, Acquired, Cost Method	(50.5)	$ (50.5)								$ (50.5)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(0.6)			$ 0.0						$ 0.9
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.3
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	10.1
Treasury Stock, Shares, Acquired		343,147								343,147
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(24.2)			$ 0.0				9.6	$ 14.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				429,611						5,402
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(156,850)
Net Income (Loss) Attributable to Parent	115.8
Dividends, Preferred Stock	(14.4)							$ (14.4)
Net Income (Loss) Attributable to Noncontrolling Interest	0.3						$ 0.3
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(69.7)					$ (69.7)
Dividends, Common Stock	(20.9)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,551,438
Additional capital	2,032.9
Retained Earnings (Accumulated Deficit)	4,462.6
Treasury Stock, Value	(1,111.8)
Stockholders' Equity Attributable to Noncontrolling Interest	(4.9)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(401.7)
Treasury stock, at cost; 23,069,535 and 22,720,986 shares in 2024 and 2023, respectively	$ (1,111.8)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					21,612
Treasury Stock, Common, Shares	23,069,535
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,977.8

REVENUE (Tables)

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue [Table Text Block]

The following tables disaggregate Wesco’s net sales by segment and geography for the periods presented:


	Three Months Ended
	March 31
(In millions)		2024		2023
Electrical & Electronic Solutions		$	2,099.0	$	2,135.1
Communications & Security Solutions		1,670.1		1,732.0
Utility & Broadband Solutions		1,580.9		1,654.8
Total by segment		$	5,350.0	$	5,521.9


	Three Months Ended
	March 31
(In millions)		2024		2023
United States		$	3,997.6	$	4,090.5
Canada		718.5		759.4
Other International(1)		633.9		672.0
Total by geography(2)		$	5,350.0	$	5,521.9

GOODWILL (Tables)

3 Months Ended

Mar. 31, 2024

Goodwill [Line Items]

Schedule of Goodwill [Table Text Block]


	Three Months Ended
	March 31, 2024
	EES		CSS		UBS		Total
	(In millions)
Beginning balance, January 1	$	838.1	$	1,211.6	$	1,212.6	$	3,262.3
Foreign currency exchange rate changes	(12.2)		(3.8)		(5.7)		(21.7)
Reclassified as assets held for sale(1)	—		—		(58.1)		(58.1)
Ending balance, March 31	$	825.9	$	1,207.8	$	1,148.8	$	3,182.5

(1) Represents the amount of goodwill that is classified as held for sale related to the sale of the WIS business, as disclosed in Note 5, “Assets and Liabilities Held for Sale”.

Schedule of Finite-Lived Intangible Assets

The components of intangible assets are as follows:


		As of
		March 31, 2024						December 31, 2023
	Life (in years)	Gross Carrying Amount (1)		Accumulated Amortization (1)		Net Carrying Amount		Gross Carrying Amount (1)		Accumulated Amortization (1)		Net Carrying Amount
Intangible assets:		(In millions)
Trademarks	Indefinite	$	792.1	$	—	$	792.1	$	793.0	$	—	$	793.0
Customer relationships	10 - 20	1,511.3		(480.5)		1,030.8		1,519.9		(464.4)		1,055.5
Distribution agreements	15 and 19	29.2		(26.5)		2.7		29.2		(26.0)		3.2
Trademarks	5 and 12	15.5		(10.1)		5.4		15.5		(9.6)		5.9
		$	2,348.1	$	(517.1)	$	1,831.0	$	2,357.6	$	(500.0)	$	1,857.6

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

The following table sets forth the remaining estimated amortization expense for intangible assets for the next five years and thereafter:


For the year ending December 31,	(In millions)
2024	$	64.0
2025	82.8
2026	77.5
2027	74.6
2028	72.9
Thereafter	667.1
Total	$	1,038.9

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

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+ Details

REVENUE Shipping and Handling Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cost of goods sold	$ 4,212.1	$ 4,313.4
Shipping and Handling [Member]
Cost of goods sold	$ 69.6	$ 76.9

Business Combinations and Asset Acquisitions (Details) - Rahi Systems - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Oct. 31, 2023
Asset Acquisition [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	$ 108.8	$ 136.3
Business Acquisition, Description of Acquired Entity	Headquartered in Fremont, California, Rahi Systems is a leading provider of global hyperscale data center solutions with over 900 employees in 25 countries.
Business Combination, Reason for Business Combination	Rahi’s expertise with complex information technology projects and global presence strengthen Wesco’s data center solution offerings.
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory			$ 19.6
BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAccountsPayable			28.0
Goodwill, Purchase Accounting Adjustments			0.9
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets			6.4
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities			6.1
us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredIncomeTaxes			$ (7.2)

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net income	$ 116.1	$ 197.2
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	45.5	44.4
Stock-based compensation expense	10.1	11.7
Amortization of Debt Issuance Costs and Discounts	4.1	3.6
Settlement	5.5	0.0
Deferred income taxes	5.2	11.6
Other operating activities, net	(0.3)	0.3
Changes in assets and liabilities
Increase (Decrease) in Accounts Receivable	116.1	133.5
Increase (Decrease) in Accounts and Other Receivables	78.9	91.5
Inventories, net	5.5	(223.8)
Increase (Decrease) in Other Operating Assets	(60.1)	(25.2)
Accounts payable	620.9	(86.5)
Accrued payroll and benefit costs	(44.0)	(149.6)
Other current and noncurrent liabilities	75.0	2.9
Net cash provided by operating activities	746.3	(255.4)
Investing Activities:
Capital expenditures	(20.4)	(13.9)
Other investing activities	3.9	1.3
Net cash used in investing activities	(16.5)	(12.6)
Financing Activities:
Proceeds from (Repayments of) Short-term Debt	0.0	(4.8)
Repayments of Senior Debt	0.0	58.6
Proceeds from issuance of long-term debt	2,470.0	968.3
Repayments of Other Long-term Debt	2,585.1	723.9
Payments for Repurchase of Common Stock	(25.2)	(51.6)
Payments for Repurchase of Common Stock	(50.0)	0.0
Payments of Ordinary Dividends, Common Stock	(20.9)	(19.2)
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	14.4	14.4
Payments of Debt Issuance Costs	(26.6)	0.0
Other financing activities, net	(2.3)	(7.2)
Net cash used in financing activities	(254.5)	88.6
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations	(13.9)	1.2
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	461.4	(178.2)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	984.1
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Disposal Group, Including Discontinued Operations		349.1
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations	985.5
Supplemental Cash Flow Information [Abstract]
Interest Paid, Excluding Capitalized Interest, Operating Activities	37.0	37.6
Income Taxes Paid	71.2	36.4
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 90.0	$ 59.9

EMPLOYEE BENEFIT PLANS Schedule of Net Benefit Costs (Tables)

3 Months Ended

Mar. 31, 2024

Postemployment Benefits [Abstract]

Schedule of Net Benefit Costs [Table Text Block]

The following table sets forth the components of net periodic pension cost for the Company’s defined benefit plans:


	Three Months Ended March 31
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	0.5	$	1.2	$	0.5	$	1.2
Interest cost	1.0		2.6		3.3		2.8		4.3		5.4
Expected return on plan assets	(0.3)		(2.4)		(3.5)		(3.0)		(3.8)		(5.4)
Recognized actuarial gain(3)	—		—		(0.1)		(0.3)		(0.1)		(0.3)
Settlement	5.5		—		—		—		5.5		—
Net periodic pension cost	$	6.2	$	0.2	$	0.2	$	0.7	$	6.4	$	0.9

(1) Defined as the Anixter Inc. Pension Plan, which was settled during the first quarter of 2024, as described below.

(3) For the three months ended March 31, 2024 and 2023, no material amounts were reclassified from accumulated other comprehensive income into net income.

FAIR VALUE (Notes)	3 Months Ended
FAIR VALUE (Notes)	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	12. FAIR VALUE OF FINANCIAL INSTRUMENTS The Company’s financial instruments primarily consist of cash and cash equivalents, accounts receivable, accounts payable, bank overdrafts, outstanding indebtedness, foreign currency forward contracts, and benefit plan assets. Except for benefit plan assets, outstanding indebtedness and foreign currency forward contracts, the carrying value of the Company’s other financial instruments approximates fair value. The assets of the Company’s various defined benefit plans primarily comprise common/collective/pool funds (i.e., mutual funds). These funds are valued at the net asset value (“NAV”) of shares held in the underlying funds. Investments for which fair value is measured using the NAV per share practical expedient are not classified in the fair value hierarchy. The Company uses a market approach to determine the fair value of its debt instruments, utilizing quoted prices in active markets, interest rates and other relevant information generated by market transactions involving similar instruments. Therefore, the inputs used to measure the fair value of the Company’s debt instruments are classified as Level 2 within the fair value hierarchy. The carrying value of Wesco’s debt instruments with fixed interest rates was $4,574.0 million and $2,823.7 million as of March 31, 2024 and December 31, 2023, respectively. The estimated fair value of this debt was $4,635.5 million and $2,880.3 million as of March 31, 2024 and December 31, 2023, respectively. The reported carrying values of Wesco’s other debt instruments, including those with variable interest rates, approximated their fair values as of March 31, 2024 and December 31, 2023. The Company purchases foreign currency forward contracts to reduce the effect of fluctuations in foreign currency-denominated accounts on its earnings. The foreign currency forward contracts are not designated as hedges for accounting purposes. The Company’s strategy is to negotiate terms for its derivatives and other financial instruments to be highly effective, such that the change in the value of the derivative offsets the impact of the underlying hedge. Its counterparties to foreign currency forward contracts have investment-grade credit ratings. The Company regularly monitors the creditworthiness of its counterparties to ensure no issues exist that could affect the value of its derivatives. The Company does not hedge 100% of its foreign currency-denominated accounts. In addition, the results of hedging can vary significantly based on various factors, such as the timing of executing foreign currency forward contracts versus the movement of currencies, as well as fluctuations in the account balances throughout each reporting period. The fair value of foreign currency forward contracts is based on the difference between the contract rate and the current price of a forward contract with an equivalent remaining term. The fair value of foreign currency forward contracts is measured using observable market information. These inputs are considered Level 2 in the fair value hierarchy. At March 31, 2024 and December 31, 2023, foreign currency forward contracts were revalued at then-current foreign exchange rates with the changes in valuation reflected directly in other non-operating expense (income) in the Condensed Consolidated Statements of Income and Comprehensive Income offsetting the transaction gain (loss) recorded on foreign currency-denominated accounts. The gross and net notional amounts of foreign currency forward contracts outstanding were approximately $203.3 million and $168.4 million, at March 31, 2024 and December 31, 2023, respectively. While all of the Company’s foreign currency forward contracts are subject to master netting arrangements with its counterparties, assets and liabilities related to these contracts are presented on a gross basis within the Condensed Consolidated Balance Sheets. The gross fair value of assets and liabilities related to foreign currency forward contracts were immaterial.
Derivatives and Fair Value	The Company purchases foreign currency forward contracts to reduce the effect of fluctuations in foreign currency-denominated accounts on its earnings. The foreign currency forward contracts are not designated as hedges for accounting purposes. The Company’s strategy is to negotiate terms for its derivatives and other financial instruments to be highly effective, such that the change in the value of the derivative offsets the impact of the underlying hedge. Its counterparties to foreign currency forward contracts have investment-grade credit ratings. The Company regularly monitors the creditworthiness of its counterparties to ensure no issues exist that could affect the value of its derivatives. The Company does not hedge 100% of its foreign currency-denominated accounts. In addition, the results of hedging can vary significantly based on various factors, such as the timing of executing foreign currency forward contracts versus the movement of currencies, as well as fluctuations in the account balances throughout each reporting period. The fair value of foreign currency forward contracts is based on the difference between the contract rate and the current price of a forward contract with an equivalent remaining term. The fair value of foreign currency forward contracts is measured using observable market information. These inputs are considered Level 2 in the fair value hierarchy. At March 31, 2024 and December 31, 2023, foreign currency forward contracts were revalued at then-current foreign exchange rates with the changes in valuation reflected directly in other non-operating expense (income) in the Condensed Consolidated Statements of Income and Comprehensive Income offsetting the transaction gain (loss) recorded on foreign currency-denominated accounts. The gross and net notional amounts of foreign currency forward contracts outstanding were approximately $203.3 million and $168.4 million, at March 31, 2024 and December 31, 2023, respectively. While all of the Company’s foreign currency forward contracts are subject to master netting arrangements with its counterparties, assets and liabilities related to these contracts are presented on a gross basis within the Condensed Consolidated Balance Sheets. The gross fair value of assets and liabilities related to foreign currency forward contracts were immaterial.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

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+ Details

SUBSEQUENT EVENTS (Details) - Subsequent Event $ in Millions	Apr. 01, 2024 USD ($)
Subsequent Event [Line Items]
Proceeds from Divestiture of Businesses	$ 338.3
Base purchase price for divestiture of business.	350.0
Minimum [Member]
Subsequent Event [Line Items]
Gain (Loss) on Disposition of Business	88.0
Maximum [Member]
Subsequent Event [Line Items]
Gain (Loss) on Disposition of Business	$ 108.0

Segment Reporting - ADJ EBITDA Reconciliations (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net Income (Loss) Available to Common Stockholders, Basic	$ 101,400,000	$ 182,700,000
Net (loss) income attributable to noncontrolling interest	300,000	100,000
Preferred Stock Dividends, Income Statement Impact	14,400,000	14,400,000
Provision for income taxes	30,900,000	44,100,000
Interest Income (Expense), Nonoperating, Net	(94,400,000)	(95,000,000.0)
Depreciation and amortization	45,500,000	44,400,000
Other Nonoperating Income (Expense)	(21,600,000)	(10,100,000)
Corporate expenses not allocated to segments	150,400,000	132,100,000
Stock-based compensation expense	10,100,000	11,700,000
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	147,000,000.0	241,300,000
EES
Other Nonoperating Income (Expense)	5,700,000	500,000
Adjusted EBITDA	$ 165,800,000	$ 183,000,000.0
Adjusted EBITDA Margin %	7.90%	8.60%
CSS
Other Nonoperating Income (Expense)	$ 18,800,000	$ 800,000
Adjusted EBITDA	$ 127,200,000	$ 155,500,000
Adjusted EBITDA Margin %	7.60%	9.00%
UBS
Other Nonoperating Income (Expense)	$ 800,000	$ 600,000
Adjusted EBITDA	$ 169,400,000	$ 187,700,000
Adjusted EBITDA Margin %	10.70%	11.30%
All Segments
Adjusted EBITDA	$ 462,400,000	$ 526,200,000
Stock-based compensation expense	$ 3,500,000	$ 3,300,000

STOCK-BASED COMPENSATION AWARDS (Details) - $ / shares	3 Months Ended
STOCK-BASED COMPENSATION AWARDS (Details) - $ / shares	Mar. 31, 2024	Mar. 31, 2023
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	0
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	202,299	170,569
Granted, Weighted Average Fair Value (in dollars per share)	$ 152.10	$ 171.03
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	192,995	208,371
Granted, Weighted Average Fair Value (in dollars per share)	$ 108.72	$ 85.94
Performance Shares [Member] \| 2020 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Weighted Average Fair Value (in dollars per share)	$ 77.08
Performance Shares [Member] \| 2023 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	80,951
Granted, Weighted Average Fair Value (in dollars per share)	$ 152.07
Performance Shares [Member] \| 2021 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	111,521
Granted, Weighted Average Fair Value (in dollars per share)	$ 77.08
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	85,425	75,182
Granted, Weighted Average Fair Value (in dollars per share)	$ 72.05	$ 76.77

Business Combinations and Asset Acquisitions	3 Months Ended
Business Combinations and Asset Acquisitions	Mar. 31, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Business Combination Disclosure	Rahi Systems Holdings, Inc. On November 1, 2022, through its wholly-owned subsidiary WESCO Distribution, Inc. (“Wesco Distribution”), the Company acquired 100% of the equity securities of Rahi Systems Holdings, Inc. (“Rahi Systems” or “Rahi”). Headquartered in Fremont, California, Rahi Systems is a leading provider of global hyperscale data center solutions with over 900 employees in 25 countries. Rahi’s expertise with complex information technology projects and global presence strengthen Wesco’s data center solution offerings. Wesco Distribution funded the purchase price paid at closing with cash on hand as well as borrowings under its accounts receivable securitization and revolving credit facilities. The estimated fair values of assets acquired and liabilities assumed were based on preliminary calculations and valuations using estimates and assumptions at the time of acquisition. As the Company obtained additional information during the measurement period, it recorded adjustments to its preliminary estimates of fair value, which were as of November 1, 2022. During the fourth quarter of 2023, the Company finalized its allocation of the purchase consideration to the respective fair values of assets acquired and liabilities assumed in the acquisition of Rahi. The Company recorded adjustments to inventories of $19.6 million, other current and non-current assets of $6.4 million, accounts payable of $28.0 million, deferred income taxes of $7.2 million, and other current and non-current liabilities of $6.1 million. The net impact of these adjustments was an increase to goodwill of $0.9 million. The results of operations of Rahi Systems are included in Wesco’s unaudited Condensed Consolidated Financial Statements beginning on November 1, 2022, the acquisition date. For the three months ended March 31, 2024 and 2023, the Condensed Consolidated Statements of Income include $108.8 million and $136.3 million of net sales, respectively, and an immaterial amount of income from operations for Rahi Systems. The Company has not presented supplemental pro forma revenue and earnings of the combined business as the acquisition of Rahi Systems is not material to Wesco’s unaudited Condensed Consolidated Financial Statements.

ACCOUNTING POLICIES (Policies)	3 Months Ended
ACCOUNTING POLICIES (Policies)	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of Wesco have been prepared in accordance with Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). The unaudited condensed consolidated financial information should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in WESCO International, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the SEC on February 20, 2024. The Condensed Consolidated Balance Sheet at December 31, 2023 was derived from the audited Consolidated Financial Statements as of that date, but does not include all the disclosures required by accounting principles generally accepted in the United States of America. The unaudited Condensed Consolidated Balance Sheet as of March 31, 2024, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Stockholders’ Equity, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2024 and 2023, respectively, in the opinion of management, have been prepared on the same basis as the audited Consolidated Financial Statements and include all adjustments necessary for the fair statement of the results of the interim periods presented herein. All adjustments reflected in the unaudited condensed consolidated financial information are of a normal recurring nature unless indicated. The results for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year.
Supplier Finance Program	Supplier Finance Programs The Company has supplier finance programs that are administered by intermediaries. Under these arrangements, participating suppliers may elect to receive early payment of invoices that have been confirmed by the Company, less an interest deduction or fees paid by the supplier, which is paid to the supplier by third-party finance providers. Wesco agrees to pay the stated amount of confirmed invoices in full on the original due date of the invoices, which is typically within 45 to 180 days of the invoice date, regardless of whether the supplier elects to receive early payment from the third-party finance providers. The Company does not provide assets pledged as security or other forms of guarantees to the finance providers or intermediaries under these arrangements. As of March 31, 2024 and December 31, 2023, the amounts due to suppliers that participate in the Company’s supplier finance program were approximately $21.7 million and $32.6 million, respectively, which are included in accounts payable in the Condensed Consolidated Balance Sheet.
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Recently Adopted and Recently Issued Accounting Standards and Disclosure Rules In September 2022, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2022-04, Supplier Finance Programs (Subtopic 405-50): Disclosure of Supplier Finance Program Obligations, which requires that a buyer in a supplier finance program disclose sufficient information about the program to allow a user of financial statements to understand the program's nature, activity during the period, changes from period to period, and potential magnitude. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, except for the amendment on rollforward information, which is effective for fiscal years beginning after December 15, 2023. The Company adopted this ASU in the first quarter of 2023, except for the amendment on rollforward information, which the Company will begin disclosing in its Annual Report on Form 10-K for the year ending December 31, 2024. The adoption of this ASU resulted in additional disclosure of the Company's supplier finance program, as described below. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which enhances prior reportable segment disclosure requirements in part by requiring entities to disclose significant expenses related to their reportable segments. The amendments in this ASU are effective on a retrospective basis for annual periods beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires disaggregated information about a reporting entity's effective tax rate reconciliation as well as information on income taxes paid to enhance the transparency and decision usefulness of income tax disclosures. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 on a prospective basis. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In March 2024, the SEC issued final climate-related disclosure rules requiring disclosure of material climate-related risks, board and management governance of such risks, and material direct and indirect greenhouse gas emissions. The rules also require disclosure in the notes to the financial statements of the effects of severe weather events and other natural conditions. Disclosures will be made prospectively, with phased-in effective dates starting with fiscal years beginning on or after January 1, 2025. In April 2024, the SEC voluntarily stayed implementation of the climate-related disclosure rules, pending completion of judicial review of consolidated challenges to the rules by the Court of Appeals for the Eighth Circuit. Management is currently evaluating the impact that these rules could have on its consolidated financial statements and notes thereto. Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to be significant to Wesco’s financial position, results of operations or cash flows.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

+ References

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+ Details

COVER PAGE - shares	3 Months Ended
COVER PAGE - shares	Mar. 31, 2024	May 01, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-14989
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	25-1723342
Entity Address, Address Line One	225 West Station Square DriveSuite 700
Entity Address, City or Town	Pittsburgh,
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15219
City Area Code	412
Local Phone Number	454-2200
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Registrant Name	WESCO International, Inc.
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Central Index Key	0000929008
Entity Common Stock, Shares Outstanding		50,827,576
Common Class A [Member]
Cover [Abstract]
Title of 12(b) Security	Common Stock, par value $.01 per share
Trading Symbol	WCC
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $.01 per share
Trading Symbol	WCC
Security Exchange Name	NYSE
Series A Preferred Stock [Member]
Cover [Abstract]
Title of 12(b) Security	Depositary Shares, each representing a 1/1,000th interest in a share of Series A Fixed-Rate Reset Cumulative Perpetual Preferred Stock
Trading Symbol	WCC PR A
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	Depositary Shares, each representing a 1/1,000th interest in a share of Series A Fixed-Rate Reset Cumulative Perpetual Preferred Stock
Trading Symbol	WCC PR A
Security Exchange Name	NYSE

Summary of Non-Qualified Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	791,627		818,284
Granted (in shares)	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	(26,413)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	(244)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	790,495
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 59.40		$ 59.55
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	0
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	63.82
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	85.35
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 59.37
Weighted Average Remaining Contractual Term, Outstanding (in years)	4 years 9 months 18 days
Aggregate Intrinsic Value, Outstanding	$ 88.6
Weighted Average Remaining Contractual Term, Exercisable (in years)	4 years 9 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 88.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 2.8
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	241,854		163,082
Granted (in shares)	85,425	75,182
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	(2,326)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	(4,327)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	77,608
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 147.20		$ 144.51
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	152.07
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	122.09
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	155.67
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 136.81
Weighted Average Remaining Contractual Term, Outstanding (in years)	8 years 10 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 5.9
Weighted Average Remaining Contractual Term, Exercisable (in years)	8 years 2 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 2.7

SCHEDULE OF EARNINGS PER SHARE, BASIC AND DILUTED (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net income (loss) attributable to WESCO International, Inc.	$ 115.8	$ 197.1
Weighted average common shares outstanding used in computing basic earnings per share (in shares)	50.9	51.0
Common shares issuable upon exercise of dilutive stock options (in shares)	1.0	1.5
Weighted average common shares outstanding and common share equivalents used in computing diluted earnings per share (in shares)	51.9	52.5
Diluted (in dollars per share)	$ 1.95	$ 3.48
Basic (in dollars per share)	$ 1.99	$ 3.58
Net Income (Loss) Available to Common Stockholders, Basic	$ 101.4	$ 182.7
Preferred Stock Dividends, Income Statement Impact	$ 14.4	$ 14.4

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

+ References

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-Section 45
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-10

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-11

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-60B

+ Details

DEBT - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended				24 Months Ended		36 Months Ended
DEBT - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2024	Mar. 15, 2029	Mar. 14, 2029	Mar. 14, 2028	Mar. 14, 2027	Mar. 14, 2026	Mar. 07, 2024	Mar. 15, 2032	Mar. 14, 2027	Dec. 31, 2023	Oct. 31, 2022
Debt Instrument [Line Items]
Percentage of principal amount of Senior Notes accelerated under default	25.00%	25.00%
Accounts Receivable Securitization Facility Amended
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity												$ 1,625,000
Debt Instrument, Maturity Date		Mar. 01, 2027
Accounts Receivable Securitization Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,550,000	$ 1,550,000
Line of Credit Facility, Opportunity to Increase Borrowing Capacity	300,000							$ 125,000
Long-term Debt	638,000	$ 638,000									$ 1,550,000
6.375% Senior Notes due 2029
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Mar. 15, 2029
Long-term Debt	$ 900,000	$ 900,000									0
Debt Instrument, Interest Rate, Stated Percentage	6.375%	6.375%
Discount percentage of par value	100.00%	100.00%
Debt Issuance Costs, Gross	$ 11,300	$ 11,300
6.375% Senior Notes due 2029 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed			100.00%		101.594%	103.188%	35.00%
6.625% Senior Notes due 2032
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Mar. 15, 2032
Long-term Debt	$ 850,000	$ 850,000									$ 0
Debt Instrument, Interest Rate, Stated Percentage	6.625%	6.625%
Debt Issuance Costs, Gross	$ 10,600	$ 10,600
6.625% Senior Notes due 2032 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				101.657%	103.313%				100.00%	35.00%

STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended	12 Months Ended
STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2027	Dec. 31, 2026	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 10.1	$ 11.7
Total unrecognized compensation cost	$ 84.1
Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 34.2	$ 2.5	$ 16.7	$ 30.7

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

SCHEDULE OF SHARE-BASED PAYMENT AWARD, VALUATION ASSUMPTIONS (Details)	3 Months Ended
	Mar. 31, 2024 Rate	Mar. 31, 2023 Rate
Share-Based Payment Arrangement [Abstract]
WESCO expected volatility	55.00%	50.00%
Risk free interest rate	4.20%	4.10%
Expected life (in years)	5 years	5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.09%	0.88%

REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	3 Months Ended
REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Deferred Revenue	$ 150.3		$ 111.9
Contract with Customer, Asset, before Allowance for Credit Loss	34.3		35.4
Deferred Revenue, Revenue Recognized	42.8	$ 21.0
Contract with Customer, Refund Liability	$ 37.4		$ 41.3

EARNINGS PER SHARE (Details) - USD ($) $ in Millions	3 Months Ended
EARNINGS PER SHARE (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury Stock, Value, Acquired, Cost Method	$ 50.5
Treasury Stock, Common [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury Stock, Shares, Acquired	343,147
Treasury Stock, Shares, Acquired	343,147
Treasury Stock, Value, Acquired, Cost Method	$ 50.5
Stock Appreciation Rights (SARs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	200,000	400,000

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 984.1	$ 524.1
Accounts Receivable, after Allowance for Credit Loss, Current	3,526.7	3,639.5
Accounts and Other Receivables, Net, Current	346.2	430.5
Inventories, net	3,525.4	3,572.1
Prepaid expenses and other current assets	286.8	225.4
Assets, Current	8,912.8	8,391.6
Property, buildings and equipment, net of accumulated depreciation of $229,041 and $213,758 in 2014 and 2013, respectively	428.1	423.6
Operating Lease, Right-of-Use Asset	768.3	761.2
Intangible assets, net	1,831.0	1,857.6
Goodwill	3,182.5	3,262.3
Other assets	311.2	322.3
Assets	15,539.0	15,060.9
Accounts payable	2,974.3	2,431.5
Accrued payroll and benefit costs	147.9	191.7
Current portion of long-term debt	11.1	8.6
Other Liabilities, Current	833.9	756.6
Liabilities, Current	4,035.9	3,388.4
Total long-term debt	5,183.8	5,313.1
Operating Lease, Liability, Noncurrent	643.5	641.7
Deferred Income Tax Liabilities, Net	457.7	451.9
Other Liabilities, Noncurrent	237.2	233.9
Liabilities	10,561.2	10,029.0
Commitments and Contingencies
Additional capital	2,032.9	2,037.1
Retained earnings	$ 4,462.6	$ 4,391.7
Treasury Stock, Common, Shares	23,069,535	22,720,986
Treasury stock, at cost; 23,069,535 and 22,720,986 shares in 2024 and 2023, respectively	$ (1,111.8)	$ (1,060.4)
Accumulated other comprehensive income	(401.7)	(332.0)
Total WESCO International, Inc. stockholders’ equity	4,982.7	5,037.1
Noncontrolling interest	(4.9)	(5.2)
Total stockholders’ equity	4,977.8	5,031.9
Liabilities and Equity	15,539.0	15,060.9
Total current assets held for sale	243.6
Asset, Held-for-Sale, Not Part of Disposal Group, Current		0.0
Deferred Income Tax Assets, Net	39.5	42.3
Disposal Group, Including Discontinued Operation, Other Assets	65.6
Asset, Held-for-Sale, Not Part of Disposal Group, Other		0.0
Total current liabilities held for sale	68.7	0.0
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	$ 3.1
Disposal Group, Including Discontinued Operation, Other Liabilities		$ 0.0
Preferred Stock
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares outstanding (in shares)	0	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	$ 0.0	$ 0.0
Series A Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized (in shares)	25,000
Preferred stock, shares outstanding (in shares)	21,612
Preferred stock, shares issued (in shares)	21,612	21,612
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	$ 0.0	$ 0.0
Common Stock [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	210,000,000	210,000,000
Common stock, shares, issued (in shares)	69,551,438	69,278,677
Common stock, shares outstanding (in shares)	50,821,334	50,897,122
Common stock	$ 0.7	$ 0.7
Common Class B [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares, issued (in shares)	4,339,431	4,339,431
Common stock, shares outstanding (in shares)	0	0
Common stock	$ 0.0	$ 0.0