0000929008-24-000029 | 10-Q | XBRL Viewer

EMPLOYEE BENEFIT PLANS (Notes)

9 Months Ended

Sep. 30, 2024

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


	Three Months Ended September 30
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	0.4	$	1.2	$	0.4	$	1.2
Interest cost	—		4.6		3.2		2.9		3.2		7.5
Expected return on plan assets	—		(4.3)		(3.2)		(3.1)		(3.2)		(7.4)
Recognized actuarial gain(3)	—		—		(0.2)		(0.3)		(0.2)		(0.3)
Settlement	(2.2)		—		—		—		(2.2)		—
Net periodic pension (benefit) cost	$	(2.2)	$	0.3	$	0.2	$	0.7	$	(2.0)	$	1.0

	Nine Months Ended September 30
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	1.4	$	3.6	$	1.4	$	3.6
Interest cost	1.1		7.8		12.5		8.6		13.6		16.4
Expected return on plan assets	(0.3)		(7.3)		(13.0)		(9.1)		(13.3)		(16.4)
Recognized actuarial gain(3)	—		—		(0.4)		(0.9)		(0.4)		(0.9)
Settlement	3.3		—		—		—		3.3		—
Net periodic pension cost	$	4.1	$	0.5	$	0.5	$	2.2	$	4.6	$	2.7

(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 and nine months ended September 30, 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 benefits of $2.4 million and $0.2 million for the three months ended September 30, 2024 and 2023, respectively, net costs of $3.2 million for the nine months ended September 30, 2024, and net benefits $0.9 million for the nine months ended September 30, 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 $1.0 million and $4.4 million was contributed during the three and nine months ended September 30, 2024, respectively. The Company did not make any contributions to its domestic qualified pension plan during the three or nine months ended September 30, 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. During the three and nine months ended September 30, 2024, the Company used $1.6 million and $8.9 million, respectively, of the excess pension plan assets to fund certain of the Company's matching contributions to the defined contribution plan in the U.S. The remaining assets related to the excess plan asset reversion are included in other current assets in the Condensed Consolidated Balance Sheet as of September 30, 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 nine months ended September 30, 2024 and are included in other current liabilities in the Condensed Consolidated Balance Sheet as of September 30, 2024.

During the first quarter of 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. During the third quarter of 2024, the Company recognized income of $2.2 million as a result of the finalization of the liabilities transferred as part of the settlement.

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 $15.9 million for the three months ended September 30, 2024 and 2023, respectively, and $58.4 million and $58.8 million for the nine months ended September 30, 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 September 30, 2024 and December 31, 2023, the Company’s obligation under the Wesco Deferred Compensation Plan was $32.5 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.

+ References

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+ Details

STOCK-BASED COMPENSATION (Tables)

9 Months Ended

Sep. 30, 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 and nine months ended September 30, 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				Nine Months Ended
	September 30, 2024		September 30, 2023		September 30, 2024		September 30, 2023
Stock options granted	—		1,593		85,425		78,729
Weighted-average fair value	n/a		$	72.57	$	72.05	$	76.69

Restricted stock units granted	1,942		1,649		240,233		175,513
Weighted-average fair value	$	150.44	$	140.91	$	157.13	$	170.13

Performance-based awards granted(1)	540		662		194,105		212,107
Weighted-average fair value(1)	$	147.26	$	115.04	$	108.94	$	86.97

(1) As described further below, the nine months ended September 30, 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 nine months ended September 30, 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 nine months ended September 30, 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	(44,063)	62.58
Forfeited	(727)	76.25
Outstanding at September 30, 2024	773,494	$	59.37	4.4	$	84.0
Exercisable at September 30, 2024	773,494	$	59.37	4.4	$	84.0

For the nine months ended September 30, 2024, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $4.7 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 nine months ended September 30, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	407,613	$	127.49
Granted	240,233	157.13
Vested	(193,762)	115.40
Forfeited	(27,973)	142.78
Unvested at September 30, 2024	426,111	$	148.54

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 nine months ended September 30, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	254,859	$	115.15
Granted(1)	194,105	108.94
Vested	(223,042)	77.08
Forfeited	(7,065)	154.19
Unvested at September 30, 2024	218,857	$	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 nine months ended September 30, 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	(3,053)	122.09
Forfeited	(6,343)	154.71
Outstanding at September 30, 2024	239,111	$	147.23	8.4	$	5.2
Exercisable at September 30, 2024	79,145	$	136.93	7.7	$	2.5

For the nine months ended September 30, 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			Nine Months Ended
	September 30, 2024	September 30, 2023		September 30, 2024		September 30, 2023
Risk free interest rate	n/a	4.4	%	4.2	%	4.1	%
Expected life (in years)	n/a	5		5		5
Expected volatility	n/a	52	%	55	%	50	%
Expected dividend yield	n/a	0.96	%	1.09	%	0.89	%

- 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 - ADJ EBITDA Reconciliations (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Corporate expenses not allocated to segments	$ 132,900,000	$ 134,900,000	$ 429,300,000	$ 409,600,000
Interest Income (Expense), Nonoperating, Net	(86,500,000)	(98,500,000)	(279,800,000)	(292,300,000)
Depreciation and amortization	46,000,000.0	45,100,000	137,600,000	136,400,000
Other Nonoperating Income (Expense)	24,900,000	(3,700,000)	99,300,000	(14,600,000)
Stock-based compensation expense	6,800,000	10,800,000	19,600,000	34,700,000
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	274,000,000.0	278,300,000	741,600,000	783,800,000
Operating Segments
Adjusted EBITDA	518,000,000.0	563,400,000	1,499,600,000	1,646,700,000
Stock-based compensation expense	3,500,000	2,900,000	10,600,000	10,000,000.0
EES
Adjusted EBITDA	186,300,000	191,500,000	547,000,000.0	563,500,000
Other Nonoperating Income (Expense)	5,600,000	1,700,000	14,300,000	12,000,000.0
EES \| Operating Segments
Adjusted EBITDA	186,300,000	191,500,000	547,000,000.0	563,500,000
CSS
Adjusted EBITDA	175,200,000	175,500,000	453,200,000	510,500,000
Other Nonoperating Income (Expense)	4,700,000	9,700,000	39,400,000	38,200,000
CSS \| Operating Segments
Adjusted EBITDA	175,200,000	175,500,000	453,200,000	510,500,000
UBS
Adjusted EBITDA	156,500,000	196,400,000	499,400,000	572,700,000
Other Nonoperating Income (Expense)	(19,700,000)	600,000	(122,100,000)	(500,000)
UBS \| Operating Segments
Adjusted EBITDA	$ 156,500,000	$ 196,400,000	$ 499,400,000	$ 572,700,000

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY Statement - USD ($) $ in Millions	Total	Treasury Stock, Common [Member]	Common Class B	Common Stock	Series A Preferred Stock	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							197.1
Dividends, Preferred Stock	(14.4)							(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)							(19.2)
Treasury Stock, Value, Acquired, Cost Method		$ (50.5)
Treasury Stock, Shares, Acquired		325,449
Net Income (Loss) Attributable to Parent	623.6
Net Income (Loss) Attributable to Noncontrolling Interest	0.0
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
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(2.4)			$ 0.0						$ 2.5
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.1
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	12.2
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(0.2)			$ 0.0				0.1	0.1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				56,044						15,895
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(1,111)
Net Income (Loss) Attributable to Parent	193.1							193.1
Dividends, Preferred Stock	(14.4)							(14.4)
Stockholders' Equity, Other								1.0
Net Income (Loss) Attributable to Noncontrolling Interest	(0.7)						(0.7)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	42.2					41.2
Dividends, Common Stock	(19.2)							(19.2)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,164,993
Additional capital	2,015.5
Retained Earnings (Accumulated Deficit)	4,093.4
Treasury Stock, Value	(984.5)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.3)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (319.5)
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	22,211,365
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,800.3
Treasury Stock, Value, Acquired, Cost Method	(50.5)									$ (50.5)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)				$ 0.0						$ 0.9
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.1
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	10.8
Treasury Stock, Shares, Acquired										325,449
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ (12.9)			$ 0.0				10.4	2.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	800,000			184,546						(5,286)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(72,194)
Net Income (Loss) Attributable to Parent	$ 233.4							233.4
Dividends, Preferred Stock	(14.4)							(14.4)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	1.1						(1.1)
Stockholders' Equity, Other							0.1	0.6
Net Income (Loss) Attributable to Noncontrolling Interest	0.6						0.6
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(63.8)					(64.5)
Dividends, Common Stock	(19.1)							(19.1)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,277,345
Additional capital	2,023.9
Retained Earnings (Accumulated Deficit)	4,283.5
Stockholders' Equity Attributable to Noncontrolling Interest	(5.7)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(384.0)
Treasury stock, at cost; 24,913,926 and 22,720,986 shares in 2024 and 2023, respectively	$ (1,035.9)
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	22,542,100
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,882.5
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; 24,913,926 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)
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
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							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)							(20.9)
Treasury Stock, Value, Acquired, Cost Method		$ (378.8)
Treasury Stock, Shares, Acquired		2,183,937
Net Income (Loss) Attributable to Parent	552.2
Dividends, Preferred Stock								(43.1)
Net Income (Loss) Attributable to Noncontrolling Interest	1.3
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)
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
Treasury Stock, Value, Acquired, Cost Method	(303.0)									$ (303.0)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(0.5)			$ 0.0						$ 0.6
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.1
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	2.7
Treasury Stock, Shares, Acquired										1,679,176
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(0.3)			$ 0.0				0.1	0.2
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				16,570						3,308
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(1,499)
Net Income (Loss) Attributable to Parent	232.1							232.1
Dividends, Preferred Stock	(14.4)							(14.4)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	1.8						(1.8)
Stockholders' Equity, Other								0.2
Net Income (Loss) Attributable to Noncontrolling Interest	0.7						0.7
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(21.7)					(21.9)
Dividends, Common Stock	(20.3)							(20.3)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,566,509
Additional capital	2,035.5
Retained Earnings (Accumulated Deficit)	4,660.1
Treasury Stock, Value	(1,415.4)
Stockholders' Equity Attributable to Noncontrolling Interest	(6.0)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (423.6)
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	24,752,019
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,851.3
Treasury Stock, Value, Acquired, Cost Method	(25.3)	$ (25.3)								$ (25.3)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(0.2)			$ 0.0
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.2
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	6.8
Treasury Stock, Shares, Acquired		161,614								161,614
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(0.1)			$ 0.0				0.0	$ 0.1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				9,433						293
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(823)
Net Income (Loss) Attributable to Parent	204.3							204.3
Dividends, Preferred Stock	(14.4)							(14.4)
Net Income (Loss) Attributable to Noncontrolling Interest	0.4						$ 0.4
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	33.8					$ 33.8
Dividends, Common Stock	(20.2)							$ (20.2)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,575,119
Additional capital	2,042.4
Retained Earnings (Accumulated Deficit)	4,829.8
Treasury Stock, Value	(1,440.7)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.6)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(389.8)
Treasury stock, at cost; 24,913,926 and 22,720,986 shares in 2024 and 2023, respectively	$ (1,440.7)
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	24,913,926
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,036.8

ACCOUNTING POLICIES (Policies)	9 Months Ended
ACCOUNTING POLICIES (Policies)	Sep. 30, 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 September 30, 2024, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Stockholders’ Equity for the three and nine months ended September 30, 2024 and 2023, and the unaudited Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 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 September 30, 2024 and December 31, 2023, the amounts due to suppliers that participate in the Company’s supplier finance programs were approximately $21.3 million and $32.6 million, respectively, which are included in accounts payable in the Condensed Consolidated Balance Sheets.
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 programs, as described above. 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 material 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476173/280-10-65-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147476176/805-60-65-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

SUBSEQUENT EVENTS (Details) - Subsequent Event - Ascent $ in Millions	Oct. 30, 2024 USD ($)
Subsequent Event [Line Items]
Business Acquisition, Date of Acquisition Agreement	Oct. 30, 2024
Business Combination, Price of Acquisition, Expected	$ 185.0

REVENUE Revenue, Performance Obligation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Cost of goods sold	$ 4,276.7	$ 4,422.4	$ 12,770.5	$ 13,238.9

INCOME TAXES	9 Months Ended
INCOME TAXES	Sep. 30, 2024
Income Tax Disclosure [Abstract]
INCOME TAXES	The effective tax rate for the three months ended September 30, 2024 and 2023 was 25.3% and 15.9%, respectively. For the three months ended September 30, 2024, the effective tax rate does not reflect any material discrete income tax benefits. For the three months ended September 30, 2023, the effective tax rate reflects discrete income tax benefits of $11.9 million resulting from the reversal of the valuation allowance against Brazilian deferred tax assets, $10.5 million relating to return-to-provision adjustments that resulted from the filing of the 2022 U.S. federal income tax return, and $7.6 million resulting from the exercise and vesting of stock-based awards. These discrete income tax benefits reduced the effective tax rate in the prior period by approximately 10.8 percentage points. The effective tax rate for the nine months ended September 30, 2024 and 2023 was 25.4% and 20.4%, respectively. For the nine months ended September 30, 2024, the effective tax rate reflects a discrete income tax benefit of $8.6 million resulting from the exercise and vesting of stock-based awards. For the nine months ended September 30, 2023, the effective tax rate reflects discrete income tax benefits of $29.7 million resulting from the exercise and vesting of stock-based awards, $11.9 million resulting from the reversal of the valuation allowance against Brazilian deferred tax assets, and $10.5 million relating to return-to-provision adjustments that resulted from the filing of the 2022 U.S. federal income tax return. These discrete income tax items reduced the effective tax rates in the respective periods by approximately 1.2 and 6.6 percentage points. 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 the Company's assessment of uncertain tax positions since December 31, 2023.

- Definition

The entire disclosure for income tax.

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+ Details

SUMMARY OF PERFORMANCE-BASED AWARDS (Details) - Performance Shares [Member] - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	218,857		218,857		254,859
Granted (in shares)	540	662	194,105	212,107
Vested (in shares)			(223,042)
Forfeited (in shares)			(7,065)
Unvested, Weighted Average Fair Value (in dollars per share)	$ 147.18		$ 147.18		$ 115.15
Granted, Weighted Average Fair Value (in dollars per share)	$ 147.26	$ 115.04	108.94	$ 86.97
Forfeited in Period, Weighted Average Fair Value (in dollars per share)			$ 154.19
2024 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Granted (in shares)			80,951
Granted, Weighted Average Fair Value (in dollars per share)			$ 152.07

DEBT (Notes)

9 Months Ended

Sep. 30, 2024

Debt Instrument [Line Items]

Debt Disclosure [Text Block]

9. DEBT

The following table sets forth Wesco's outstanding indebtedness:


	As of
	September 30, 2024		December 31, 2023
	(In millions)
International lines of credit	$	0.8	$	1.0
Accounts Receivable Securitization Facility	1,450.0		1,550.0
Revolving Credit Facility	485.0		953.0
6.00% Anixter Senior Notes due 2025	4.2		4.2
7.125% Senior Notes due 2025	—		1,500.0
7.250% Senior Notes due 2028, less debt discount of $4.7 and $5.6 in 2024 and 2023, respectively	1,320.3		1,319.4
6.375% Senior Notes due 2029	900.0		—
6.625% Senior Notes due 2032	850.0		—
Finance lease obligations	58.2		31.4
Total debt	5,068.5		5,359.0
Plus: Fair value adjustments to the Anixter Senior Notes	0.1		0.1
Less: Unamortized debt issuance costs	(45.9)		(37.4)
Less: Short-term debt and current portion of long-term debt	(14.9)		(8.6)
Total long-term debt	$	5,007.8	$	5,313.1

Accounts Receivable Securitization Facility

On March 8, 2024, Wesco Distribution amended its accounts receivable securitization facility (the “Receivables Facility”) pursuant to the terms and conditions of an Eighth Amendment to Fifth Amended and Restated Receivables Purchase Agreement (the “Eighth Receivables Amendment”), by and among WESCO Receivables Corp., Wesco Distribution, the various purchasers and purchaser agents party thereto and PNC Bank, National Association, as administrator. The Eighth Receivables Amendment modified the receivables purchase agreement originally entered into on June 22, 2020 (the “Receivables Purchase Agreement”). The Eighth Receivables Amendment, among other things, (i) reduced the purchase limit under the Receivables Facility from $1,625 million to $1,550 million, (ii) increased the capacity to request increases in the purchase limit under the Receivables Facility from $125 million to $300 million, (iii) extended the termination date of the Receivables Facility to March 1, 2027, (iv) added a commercial paper funding option for any conduit purchaser funding its investment through issuances of notes, and (v) modified the drawn spread applicable to investments. No other material terms were changed.

Revolving Credit Facility

On March 6, 2024, Wesco Distribution amended its revolving credit facility (the “Revolving Credit Facility”) pursuant to the terms and conditions of a Sixth Amendment to Fourth Amended and Restated Credit Agreement (the “Sixth Revolver Amendment”). The Sixth Revolver Amendment amended the Revolving Credit Agreement to, among other things, modify the Canadian interest rate options and increase certain negative covenant baskets. No other material terms were changed.

7.125% Senior Notes due 2025

In June 2020, Wesco Distribution issued $1,500 million aggregate principal amount of 7.125% Senior Notes due 2025 (the “2025 Notes”) through a private offering exempt from the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”). The 2025 Notes were issued at a price of 100% of the aggregate principal amount and were issued pursuant to, and governed by, an indenture (the “2025 Notes Indenture”), dated as of June 12, 2020, between the Company, Wesco Distribution, and U.S. Bank National Association, as trustee. The 2025 Notes were unsecured and unsubordinated obligations of Wesco Distribution and were guaranteed on an unsecured, unsubordinated basis by the Company and Anixter Inc. The 2025 Notes had a stated interest rate of 7.125% per annum, payable semi-annually in arrears on June 15 and December 15 of each year. The 2025 Notes had a maturity date of June 15, 2025 and were redeemable in whole or in part at a redemption price equal to 101.781% of the principal amount between June 15, 2023 and June 14, 2024 or 100% of the principal amount on and after June 15, 2024. The net proceeds from the issuance of the 2025 Notes, together with other borrowings and existing cash on hand, were used to finance the merger with Anixter Inc.

On May 20, 2024, Wesco Distribution exercised its right to redeem the entire outstanding $1,500 million aggregate principal amount of the 2025 Notes, and U.S. Bank Trust Company, National Association, as successor to U.S. Bank National Association, as trustee under the 2025 Notes Indenture, issued a notice of redemption to registered holders of the 2025 Notes.

On June 17, 2024, Wesco Distribution redeemed the $1,500 million aggregate principal amount of the 2025 Notes at a redemption price equal to 100% of the principal amount plus accrued interest up to, but not including, June 15, 2024. The redemption of the 2025 Notes was funded through the issuance of the 6.375% Senior Notes due 2029 (the “2029 Notes”) and the 6.625% Senior Notes due 2032 (the “2032 Notes” and, together with the 2029 Notes, the “2029 and 2032 Notes”) as described below. The Company recognized a non-cash loss of $6.8 million from the redemption of the 2025 Notes resulting from the write-off of unamortized debt issuance costs, which is recorded as a component of interest expense, net in the Condensed Consolidated Statement of Income and Comprehensive Income for the nine months ended September 30, 2024.

6.375% Senior Notes due 2029

6.625% Senior Notes due 2032

On March 7, 2024, Wesco Distribution issued $900 million aggregate principal amount of 6.375% senior notes due 2029 and $850 million aggregate principal amount of 6.625% senior notes due 2032. The 2029 and 2032 Notes were issued at a price of 100% of the aggregate principal amount. Wesco incurred costs related to the issuance of the 2029 Notes and 2032 Notes totaling $11.3 million and $10.6 million, respectively, which were recorded as a reduction to the carrying value of the debt and are being amortized over the respective lives of the notes.

The 2029 and 2032 Notes were issued pursuant to, and are governed by, an indenture (the “2029 and 2032 Notes Indenture”), dated as of March 7, 2024, among Wesco Distribution, the Company, Anixter Inc., and U.S. Bank Trust Company, National Association, as trustee (the “Trustee”). The 2029 and 2032 Notes and related guarantees were issued in a private transaction exempt from the Securities Act.

The Company used the net proceeds from the issuance of the 2029 and 2032 Notes to redeem the 2025 Notes on June 17, 2024. Prior to repaying the 2025 Notes, the Company used the net proceeds temporarily to repay a portion of the amounts outstanding under its Receivables Facility and repaid all of the outstanding borrowings under its Revolving Credit Facility. The Company subsequently redrew under the Receivables Facility and the Revolving Credit Facility an aggregate amount sufficient to redeem the 2025 Notes.

The 2029 and 2032 Notes are unsecured and unsubordinated obligations of Wesco Distribution and are guaranteed on an unsecured, unsubordinated basis by the Company and Anixter Inc. The 2029 Notes accrue interest at a rate of 6.375% per annum, payable semi-annually in arrears on March 15 and September 15 of each year. The 2029 Notes will mature on March 15, 2029. The 2032 Notes accrue interest at a rate of 6.625% per annum, payable semi-annually in arrears on March 15 and September 15 of each year. The 2032 Notes will mature on March 15, 2032.

Wesco Distribution may redeem all or a part of the 2029 Notes at any time prior to March 15, 2026 by paying a “make-whole” premium plus accrued and unpaid interest, if any, to but excluding the redemption date. In addition, at any time prior to March 15, 2026, Wesco Distribution may redeem up to 35% of the original aggregate principal amount of the 2029 Notes with the net cash proceeds from certain equity offerings. At any time between March 15, 2026 and March 14, 2027, Wesco Distribution may redeem all or a part of the 2029 Notes at a redemption price equal to 103.188% of the principal amount. Between March 15, 2027 and March 14, 2028, Wesco Distribution may redeem all or a part of the 2029 Notes at a redemption price equal to 101.594% of the principal amount. On and after March 15, 2028, Wesco Distribution may redeem all or a part of the 2029 Notes at a redemption price equal to 100% of the principal amount.

Wesco Distribution may redeem all or a part of the 2032 Notes at any time prior to March 15, 2027 by paying a “make-whole” premium plus accrued and unpaid interest, if any, to but excluding the redemption date. In addition, at any time prior to March 15, 2027, Wesco Distribution may redeem up to 35% of the original aggregate principal amount of the 2032 Notes with the net cash proceeds from certain equity offerings. At any time between March 15, 2027 and March 14, 2028, Wesco Distribution may redeem all or a part of the 2032 Notes at a redemption price equal to 103.313% of the principal amount. Between March 15, 2028 and March 14, 2029, Wesco Distribution may redeem all or a part of the 2032 Notes at a redemption price equal to 101.657% of the principal amount. On and after March 15, 2029, Wesco Distribution may redeem all or a part of the 2032 Notes at a redemption price equal to 100% of the principal amount.

The 2029 and 2032 Notes Indenture contains certain covenants that, among other things, limit the Company’s and its restricted subsidiaries’ ability to incur liens on assets, make certain restricted payments, engage in certain sale and leaseback transactions or sell certain assets or merge or consolidate with or into other companies, subject to certain qualifications and exceptions, including the termination of certain of these covenants upon the 2029 and 2032 Notes receiving investment grade credit ratings.

The 2029 and 2032 Notes Indenture contains certain events of default, including, among other things, failure to make required payments, failure to comply with certain agreements or covenants, failure to pay or acceleration of certain other indebtedness, certain events of bankruptcy and insolvency, and failure to pay certain judgments. An event of default under the 2029 and 2032 Notes Indenture will allow either the Trustee or the holders of at least 25% in aggregate principal amount of the applicable series of the then-outstanding Notes to accelerate or, in certain cases, will automatically cause the acceleration of the amounts due under the applicable series of Notes.

- 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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+ Details

Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Segment Reporting (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 5,489.4	$ 5,644.4	$ 16,319.1	$ 16,911.8
Depreciation, Depletion and Amortization	46.0	45.1	137.6	136.4
Other Nonoperating Income (Expense)	24.9	(3.7)	99.3	(14.6)
Assets	15,275.0		15,275.0		$ 15,060.9
EES
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,151.2	2,190.7	6,423.1	6,526.1
Adjusted EBITDA	$ 186.3	$ 191.5	$ 547.0	$ 563.5
Adjusted EBITDA Margin %	8.70%	8.70%	8.50%	8.60%
Depreciation, Depletion and Amortization	$ 12.2	$ 10.9	$ 34.8	$ 32.3
Other Nonoperating Income (Expense)	5.6	1.7	14.3	12.0
Assets	4,648.2		4,648.2		4,553.6
CSS
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,955.1	1,778.0	5,491.1	5,360.9
Adjusted EBITDA	$ 175.2	$ 175.5	$ 453.2	$ 510.5
Adjusted EBITDA Margin %	9.00%	9.90%	8.30%	9.50%
Depreciation, Depletion and Amortization	$ 17.6	$ 18.0	$ 53.9	$ 53.9
Other Nonoperating Income (Expense)	4.7	9.7	39.4	38.2
Assets	5,830.7		5,830.7		5,626.6
UBS
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,383.1	1,675.7	4,404.9	5,024.8
Adjusted EBITDA	$ 156.5	$ 196.4	$ 499.4	$ 572.7
Adjusted EBITDA Margin %	11.30%	11.70%	11.30%	11.40%
Depreciation, Depletion and Amortization	$ 6.9	$ 6.3	$ 21.3	$ 18.7
Other Nonoperating Income (Expense)	(19.7)	0.6	(122.1)	(0.5)
Assets	3,671.1		3,671.1		3,908.5
Corporate Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation, Depletion and Amortization	9.3	9.9	27.6	31.5
Other Nonoperating Income (Expense)	(15.5)	$ 8.3	(30.9)	$ (35.1)
Assets	$ 1,125.0		$ 1,125.0		$ 972.2

REVENUE (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 135.0		$ 135.0		$ 111.9
Revenue from Contract with Customer, Excluding Assessed Tax	5,489.4	$ 5,644.4	16,319.1	$ 16,911.8
Cost of goods sold	4,276.7	4,422.4	12,770.5	13,238.9
Contract with Customer, Refund Liability	41.0		41.0		$ 41.3
EES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,151.2	2,190.7	6,423.1	6,526.1
CSS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,955.1	1,778.0	5,491.1	5,360.9
UBS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,383.1	1,675.7	4,404.9	5,024.8
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,041.4	4,166.5	12,089.5	12,529.5
CANADA
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	763.7	765.8	2,226.6	2,298.3
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	684.3	712.1	2,003.0	2,084.0
Shipping and Handling [Member]
Disaggregation of Revenue [Line Items]
Cost of goods sold	$ 80.9	$ 76.4	$ 226.2	$ 232.4

EMPLOYEE BENEFIT PLANS Schedule of Net Benefit Costs (Tables)

9 Months Ended

Sep. 30, 2024

Postemployment Benefits [Abstract]

Schedule of Net Benefit Costs [Table Text Block]

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


	Three Months Ended September 30
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	0.4	$	1.2	$	0.4	$	1.2
Interest cost	—		4.6		3.2		2.9		3.2		7.5
Expected return on plan assets	—		(4.3)		(3.2)		(3.1)		(3.2)		(7.4)
Recognized actuarial gain(3)	—		—		(0.2)		(0.3)		(0.2)		(0.3)
Settlement	(2.2)		—		—		—		(2.2)		—
Net periodic pension (benefit) cost	$	(2.2)	$	0.3	$	0.2	$	0.7	$	(2.0)	$	1.0

	Nine Months Ended September 30
(In millions)	2024		2023		2024		2023		2024		2023
	Domestic Plan(1)				Foreign Plans(2)				Total
Service cost	$	—	$	—	$	1.4	$	3.6	$	1.4	$	3.6
Interest cost	1.1		7.8		12.5		8.6		13.6		16.4
Expected return on plan assets	(0.3)		(7.3)		(13.0)		(9.1)		(13.3)		(16.4)
Recognized actuarial gain(3)	—		—		(0.4)		(0.9)		(0.4)		(0.9)
Settlement	3.3		—		—		—		3.3		—
Net periodic pension cost	$	4.1	$	0.5	$	0.5	$	2.2	$	4.6	$	2.7

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

(3) For the three and nine months ended September 30, 2024 and 2023, no material amounts were reclassified from accumulated other comprehensive income into net income.

REVENUE (Notes)

9 Months Ended

Sep. 30, 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				Nine Months Ended
	September 30				September 30
(In millions)	2024		2023		2024		2023
Electrical & Electronic Solutions	$	2,151.2	$	2,190.7	$	6,423.1	$	6,526.1
Communications & Security Solutions	1,955.1		1,778.0		5,491.1		5,360.9
Utility & Broadband Solutions	1,383.1		1,675.7		4,404.9		5,024.8
Total by segment	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8


	Three Months Ended				Nine Months Ended
	September 30				September 30
(In millions)	2024		2023		2024		2023
United States	$	4,041.4	$	4,166.5	$	12,089.5	$	12,529.5
Canada	763.7		765.8		2,226.6		2,298.3
Other International(1)	684.3		712.1		2,003.0		2,084.0
Total by geography(2)	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8

(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 and receives payment from its customers in advance of satisfying the respective performance obligation. Such advance billings and 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 and payment. At September 30, 2024 and December 31, 2023, $135.0 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 $3.2 million and $60.3 million of revenue during the three and nine months ended September 30, 2024, respectively, that was included in the deferred revenue balance as of December 31, 2023, and recognized $22.1 million and $64.1 million of revenue during the three and nine months ended September 30, 2023, respectively, that was included in the deferred revenue balance as of December 31, 2022.

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 September 30, 2024 and December 31, 2023, the Company had contract assets of $40.7 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 by approximately $110.4 million and $118.4 million, for the three months ended September 30, 2024 and 2023, respectively, and by approximately $331.2 million and $333.5 million for the nine months ended September 30, 2024 and 2023, respectively. As of September 30, 2024 and December 31, 2023, the Company's estimated product return obligation was $41.0 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 $80.9 million and $76.4 million for the three months ended September 30, 2024 and 2023, respectively, and $226.2 million and $232.4 million for the nine months ended September 30, 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

SCHEDULE OF EARNINGS PER SHARE, BASIC AND DILUTED (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Net income (loss) attributable to WESCO International, Inc.	$ 204.3	$ 232.1	$ 115.8	$ 233.4	$ 193.1	$ 197.1	$ 552.2	$ 623.6
Weighted average common shares outstanding used in computing basic earnings per share (in shares)	49.1			51.2			50.0	51.2
Common shares issuable upon exercise of dilutive stock options (in shares)	0.7			1.0			0.8	1.2
Weighted average common shares outstanding and common share equivalents used in computing diluted earnings per share (in shares)	49.8			52.2			50.8	52.4
Diluted (in dollars per share)	$ 3.81			$ 4.20			$ 10.02	$ 11.08
Basic (in dollars per share)	$ 3.87			$ 4.28			$ 10.18	$ 11.34
Net Income (Loss) Available to Common Stockholders, Basic	$ 189.9			$ 219.0			$ 509.1	$ 580.5
Preferred Stock Dividends, Income Statement Impact	$ 14.4			$ 14.4			$ 43.1	$ 43.1

- 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

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+ 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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+ Details

Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands				3 Months Ended	9 Months Ended
	Jul. 01, 2024	Jun. 03, 2024	Apr. 01, 2024	Sep. 30, 2024	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Asset Acquisition [Line Items]
Goodwill				$ 3,217,700	$ 3,217,700		$ 3,262,300
Proceeds from Divestiture of Businesses, Net of Cash Divested			$ 334,200		354,900	$ 0
Base purchase price for divestiture of business.			$ 350,000
Gain (Loss) on Disposition of Business				19,300	122,200	$ 0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred				20,700
entroCIM
Asset Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Jun. 03, 2024
Fair value of cash consideration					30,100
Total purchase consideration					36,500
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				8,000	8,000
Business Combination, Contingent Consideration, Liability				6,400	6,400
Intangible assets				8,000	8,000
Goodwill				29,000	29,000
Ascent
Asset Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Jul. 01, 2024
Fair value of cash consideration					11,600
Total purchase consideration					13,200
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 2,900
Intangible assets				$ 5,900	$ 5,900

STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended			5 Months Ended	9 Months Ended		12 Months Ended
STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	Dec. 31, 2024	Sep. 30, 2024	Sep. 30, 2023	May 31, 2028	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2027	Dec. 31, 2026	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 6.8	$ 10.8		$ 19.6	$ 34.7
Total unrecognized compensation cost		$ 60.4			$ 60.4
Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 10.1			$ 0.3			$ 3.7	$ 18.0	$ 28.3

- 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

Segment Reporting (Tables)

9 Months Ended

Sep. 30, 2024

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

The following table sets forth net sales by reportable segment for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	2,151.2	$	2,190.7	$	6,423.1	$	6,526.1
CSS	1,955.1		1,778.0		5,491.1		5,360.9
UBS	1,383.1		1,675.7		4,404.9		5,024.8
Total	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8

The following table sets forth adjusted EBITDA and adjusted EBITDA margin % by reportable segment for the periods presented:


	Three Months Ended September 30						Nine Months Ended September 30
(In millions)	2024			2023			2024			2023
EES	$	186.3		$	191.5		$	547.0		$	563.5
Adjusted EBITDA Margin	8.7		%	8.7		%	8.5		%	8.6		%
CSS	$	175.2		$	175.5		$	453.2		$	510.5
Adjusted EBITDA Margin	9.0		%	9.9		%	8.3		%	9.5		%
UBS	$	156.5		$	196.4		$	499.4		$	572.7
Adjusted EBITDA Margin	11.3		%	11.7		%	11.3		%	11.4		%

The following table sets forth depreciation and amortization by reportable segment for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	12.2	$	10.9	$	34.8	$	32.3
CSS	17.6		18.0		53.9		53.9
UBS	6.9		6.3		21.3		18.7
Corporate	9.3		9.9		27.6		31.5
Total	$	46.0	$	45.1	$	137.6	$	136.4

The following table sets forth other (income) expense, net by reportable segment for the periods presented, which primarily consists of net foreign currency exchange (gains) losses and the gain on the divestiture of the WIS business:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	5.6	$	1.7	$	14.3	$	12.0
CSS	4.7		9.7		39.4		38.2
UBS	(19.7)		0.6		(122.1)		(0.5)
Corporate	(15.5)		(8.3)		(30.9)		(35.1)
Total	$	(24.9)	$	3.7	$	(99.3)	$	14.6

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


	As of
(In millions)	September 30, 2024		December 31, 2023
EES	$	4,648.2	$	4,553.6
CSS	5,830.7		5,626.6
UBS	3,671.1		3,908.5
Corporate(1)	1,125.0		972.2
Total	$	15,275.0	$	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 assets.

The following table reconciles adjusted EBITDA by segment to income before income taxes, for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
Adjusted EBITDA by segment
EES	$	186.3	$	191.5	$	547.0	$	563.5
CSS	175.2		175.5		453.2		510.5
UBS	156.5		196.4		499.4		572.7
Total segment adjusted EBITDA	518.0		563.4		1,499.6		1,646.7
Less:
Corporate expenses not allocated to segments	132.9		134.9		429.3		409.6
Interest expense, net	86.5		98.5		279.8		292.3
Depreciation and amortization	46.0		45.1		137.6		136.4
Other (income) expense, net	(24.9)		3.7		(99.3)		14.6
Stock-based compensation expense allocated to segments	3.5		2.9		10.6		10.0
Income before income taxes	$	274.0	$	278.3	$	741.6	$	783.8

STOCK-BASED COMPENSATION (Notes)

9 Months Ended

Sep. 30, 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, typically 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.


	Three Months Ended				Nine Months Ended
	September 30, 2024		September 30, 2023		September 30, 2024		September 30, 2023
Stock options granted	—		1,593		85,425		78,729
Weighted-average fair value	n/a		$	72.57	$	72.05	$	76.69

Restricted stock units granted	1,942		1,649		240,233		175,513
Weighted-average fair value	$	150.44	$	140.91	$	157.13	$	170.13

Performance-based awards granted(1)	540		662		194,105		212,107
Weighted-average fair value(1)	$	147.26	$	115.04	$	108.94	$	86.97

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			Nine Months Ended
	September 30, 2024	September 30, 2023		September 30, 2024		September 30, 2023
Risk free interest rate	n/a	4.4	%	4.2	%	4.1	%
Expected life (in years)	n/a	5		5		5
Expected volatility	n/a	52	%	55	%	50	%
Expected dividend yield	n/a	0.96	%	1.09	%	0.89	%

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 nine months ended September 30, 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	(3,053)	122.09
Forfeited	(6,343)	154.71
Outstanding at September 30, 2024	239,111	$	147.23	8.4	$	5.2
Exercisable at September 30, 2024	79,145	$	136.93	7.7	$	2.5

For the nine months ended September 30, 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 nine months ended September 30, 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	(44,063)	62.58
Forfeited	(727)	76.25
Outstanding at September 30, 2024	773,494	$	59.37	4.4	$	84.0
Exercisable at September 30, 2024	773,494	$	59.37	4.4	$	84.0

For the nine months ended September 30, 2024, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $4.7 million.

The following table sets forth a summary of restricted stock units and related information for the nine months ended September 30, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	407,613	$	127.49
Granted	240,233	157.13
Vested	(193,762)	115.40
Forfeited	(27,973)	142.78
Unvested at September 30, 2024	426,111	$	148.54

The following table sets forth a summary of performance-based awards and related information for the nine months ended September 30, 2024:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2023	254,859	$	115.15
Granted(1)	194,105	108.94
Vested	(223,042)	77.08
Forfeited	(7,065)	154.19
Unvested at September 30, 2024	218,857	$	147.18

Wesco recognized $6.8 million and $10.8 million of non-cash stock-based compensation expense for the three months ended September 30, 2024 and 2023, respectively, and $19.6 million and $34.7 million of non-cash stock-based compensation expense for the nine months ended September 30, 2024 and 2023, respectively, which is included in selling, general and administrative expenses for such periods. As of September 30, 2024, there was $60.4 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:


For the year ending December 31,	(In millions)
Remaining 2024	$	10.1
2025	28.3
2026	18.0
2027	3.7
2028	0.3

REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Deferred Revenue	$ 135.0		$ 135.0		$ 111.9
Contract with Customer, Asset, before Allowance for Credit Loss	40.7		40.7		35.4
Deferred Revenue, Revenue Recognized	3.2	$ 22.1	60.3	$ 64.1
Contract with Customer, Refund Liability	$ 41.0		$ 41.0		$ 41.3

EMPLOYEE BENEFIT PLANS - Components of Net Periodic Penson Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.4	$ 1.2	$ 1.4	$ 3.6
Interest cost	3.2	7.5	13.6	16.4
Expected return on plan assets	(3.2)	(7.4)	(13.3)	(16.4)
Recognized actuarial gain	(0.2)	(0.3)	(0.4)	(0.9)
Pension Cost (Reversal of Cost)	(2.2)	0.0	3.3	0.0
Net periodic pension (benefit) cost	(2.0)	1.0	4.6	2.7
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Nonoperating Gains (Losses)	(2.4)	(0.2)	3.2	(0.9)
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0	0.0	0.0
Interest cost	0.0	4.6	1.1	7.8
Expected return on plan assets	0.0	(4.3)	(0.3)	(7.3)
Recognized actuarial gain	0.0	0.0	0.0	0.0
Pension Cost (Reversal of Cost)	(2.2)	0.0	3.3	0.0
Net periodic pension (benefit) cost	(2.2)	0.3	4.1	0.5
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.4	1.2	1.4	3.6
Interest cost	3.2	2.9	12.5	8.6
Expected return on plan assets	(3.2)	(3.1)	(13.0)	(9.1)
Recognized actuarial gain	(0.2)	(0.3)	(0.4)	(0.9)
Pension Cost (Reversal of Cost)	0.0	0.0	0.0	0.0
Net periodic pension (benefit) cost	$ 0.2	$ 0.7	$ 0.5	$ 2.2

REVENUE (Tables)

9 Months Ended

Sep. 30, 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				Nine Months Ended
	September 30				September 30
(In millions)	2024		2023		2024		2023
Electrical & Electronic Solutions	$	2,151.2	$	2,190.7	$	6,423.1	$	6,526.1
Communications & Security Solutions	1,955.1		1,778.0		5,491.1		5,360.9
Utility & Broadband Solutions	1,383.1		1,675.7		4,404.9		5,024.8
Total by segment	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8


	Three Months Ended				Nine Months Ended
	September 30				September 30
(In millions)	2024		2023		2024		2023
United States	$	4,041.4	$	4,166.5	$	12,089.5	$	12,529.5
Canada	763.7		765.8		2,226.6		2,298.3
Other International(1)	684.3		712.1		2,003.0		2,084.0
Total by geography(2)	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8

CONSOLIDATED BALANCE SHEETS (parenthetical items) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Total accounts receivable, net of allowance for expected credit losses	$ 61.0	$ 55.9
Accumulated depreciation	532.8	502.5
Long-term debt, net of debt discount and debt issuance costs	$ 50.6	$ 43.0
Treasury Stock, Common, Shares	24,913,926	22,720,986
Preferred Stock
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, par value (in dollars per share)	$ 0.01	$ 0.01
Series A Preferred Stock
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, par value (in dollars per share)	$ 0.01
Common Stock
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)	69,575,119	69,278,677
Common stock, shares outstanding (in shares)	49,000,624	50,897,122
Common Class B
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

INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
INCOME TAXES (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Contingency [Line Items]
Effective tax rate	25.30%	15.90%	25.40%	20.40%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount		$ 7.6	$ 8.6
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		$ 11.9		$ 11.9
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 10.5			$ 10.5
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Percent				2970000000.00%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent		1080.00%	120.00%	660.00%

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Gross Profit [Abstract]
Revenues	$ 5,489.4	$ 5,644.4	$ 16,319.1	$ 16,911.8
Cost of goods sold	4,276.7	4,422.4	12,770.5	13,238.9
Operating Expenses [Abstract]
Selling, general and administrative expense	831.1	796.4	2,488.9	2,445.8
Depreciation and amortization	46.0	45.1	137.6	136.4
Income from operations	335.6	380.5	922.1	1,090.7
Interest Income (Expense), Nonoperating, Net	86.5	98.5	279.8	292.3
Other Nonoperating Income (Expense)	(24.9)	3.7	(99.3)	14.6
Income before income taxes	274.0	278.3	741.6	783.8
Provision for income taxes	69.3	44.3	188.1	160.2
Net income	204.7	234.0	553.5	623.6
Net (loss) income attributable to noncontrolling interest	0.4	0.6	1.3	0.0
Net income attributable to WESCO International, Inc.	204.3	233.4	552.2	623.6
Preferred Stock Dividends, Income Statement Impact	14.4	14.4	43.1	43.1
Net Income (Loss) Available to Common Stockholders, Basic	$ 189.9	$ 219.0	$ 509.1	$ 580.5
Basic (in dollars per share)	$ 3.87	$ 4.28	$ 10.18	$ 11.34
Diluted (in dollars per share)	$ 3.81	$ 4.20	$ 10.02	$ 11.08
Comprehensive Income:
Foreign currency translation adjustment	$ 33.9	$ (64.5)	$ (59.5)	$ (6.3)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(0.1)	0.0	1.7	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	33.8	(64.5)	(57.8)	(6.3)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	238.5	169.5	495.7	617.3
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0.4	0.6	1.3	0.0
Comprehensive income attributable to WESCO International, Inc.	$ 223.7	$ 154.5	$ 451.3	$ 574.2

DEBT - Narrative (Details) - USD ($) $ in Thousands	7 Months Ended	9 Months Ended	12 Months Ended						24 Months Ended		36 Months Ended
DEBT - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2024	Mar. 15, 2029	Mar. 14, 2029	Mar. 14, 2028	Mar. 14, 2027	Jun. 14, 2025	Jun. 14, 2024	Mar. 14, 2026	Mar. 07, 2024	Mar. 15, 2032	Mar. 14, 2027	Dec. 31, 2023
Debt Instrument [Line Items]
Gain (Loss) on Extinguishment of Debt		$ 6,800
Percentage of principal amount of Senior Notes accelerated under default	25.00%	25.00%
Accounts Receivable Securitization Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,550,000	$ 1,550,000											$ 1,625,000
Line of Credit Facility, Opportunity to Increase Borrowing Capacity	300,000									$ 125,000
Debt Instrument, Maturity Date		Mar. 01, 2027
6.375% Senior Notes due 2029
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Mar. 15, 2029
Debt Instrument, Face Amount	$ 900,000	$ 900,000
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
Debt Instrument, Face Amount	$ 850,000	$ 850,000
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%
7.125% Senior Notes due 2025
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Jun. 15, 2025
Debt Instrument, Face Amount													$ 1,500,000
Debt Instrument, Interest Rate, Stated Percentage													7.125%
Discount percentage of par value													100.00%
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed		100.00%						101.781%
7.125% Senior Notes due 2025 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed							100.00%

REVENUE Shipping and Handling Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Cost of goods sold	$ 4,276.7	$ 4,422.4	$ 12,770.5	$ 13,238.9
Shipping and Handling [Member]
Cost of goods sold	$ 80.9	$ 76.4	$ 226.2	$ 232.4

STOCK-BASED COMPENSATION AWARDS (Details) - $ / shares	3 Months Ended		9 Months Ended
STOCK-BASED COMPENSATION AWARDS (Details) - $ / shares	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 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)	1,942	1,649	240,233	175,513
Granted, Weighted Average Fair Value (in dollars per share)	$ 150.44	$ 140.91	$ 157.13	$ 170.13
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	540	662	194,105	212,107
Granted, Weighted Average Fair Value (in dollars per share)	$ 147.26	$ 115.04	$ 108.94	$ 86.97
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] \| 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)	0	1,593	85,425	78,729
Granted, Weighted Average Fair Value (in dollars per share)		$ 72.57	$ 72.05	$ 76.69

- 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

FAIR VALUE (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative, Notional Amount	$ 354.3	$ 168.4
Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value	3,177.8	2,880.3
Long-term Debt	$ 3,074.6	$ 2,823.7

- Definition

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

+ References + Details

COVER PAGE - shares	9 Months Ended
COVER PAGE - shares	Sep. 30, 2024	Oct. 30, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 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	Q3
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Central Index Key	0000929008
Entity Common Stock, Shares Outstanding		49,001,657
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
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

Equity

9 Months Ended

Sep. 30, 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 and nine months ended September 30, 2024, the Company entered into spot repurchase transactions through brokers to purchase 161,614 and 2,183,937 shares, respectively, of its common stock in the open market for cash totaling $25.3 million and $378.8 million, respectively, including excise taxes. Wesco funded the repurchases with available cash and borrowings under its accounts receivable securitization and revolving credit facilities. During the three and nine months ended September 30, 2023, the Company entered into spot repurchase transactions through a broker to purchase 325,449 shares of its common stock totaling $50.5 million, including excise taxes. Wesco funded the repurchases with available cash and borrowings under its revolving credit facility.

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 nine months ended September 30, 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
May 30, 2024	June 14, 2024	June 28, 2024	$	0.413	$	20.3	million
August 29, 2024	September 13, 2024	September 30, 2024	$	0.413	$	20.2	million

The following table is a summary of cash dividends declared and paid on the Company’s common stock for the nine months ended September 30, 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
June 1, 2023	June 15, 2023	June 30, 2023	$	0.375	$	19.2	million
August 31, 2023	September 15, 2023	September 29, 2023	$	0.375	$	19.1	million

During the three and nine months ended September 30, 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 and $43.1 million, respectively, each year.

- Definition

The entire disclosure for equity.

+ References

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+ Details

FAIR VALUE (Notes)	9 Months Ended
FAIR VALUE (Notes)	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	11. 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 $3,074.6 million and $2,823.7 million as of September 30, 2024 and December 31, 2023, respectively. The estimated fair value of this debt was $3,177.8 million and $2,880.3 million as of September 30, 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 September 30, 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 September 30, 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 $354.3 million and $168.4 million, at September 30, 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 September 30, 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 $354.3 million and $168.4 million, at September 30, 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

GOODWILL (Tables)

9 Months Ended

Sep. 30, 2024

Goodwill [Line Items]

Schedule of Goodwill [Table Text Block]


	Nine Months Ended
	September 30, 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	(11.8)		(1.8)		(5.4)		(19.0)
Adjustments to goodwill for acquisitions(1)	3.5		29.0		—		32.5
Adjustment to goodwill for divestiture(2)	—		—		(58.1)		(58.1)
Ending balance, September 30	$	829.8	$	1,238.8	$	1,149.1	$	3,217.7

(1) Reflects the preliminary allocation of the purchase price paid to acquire IES and entroCIM, which are part of the EES and CSS segments, respectively, as described in Note 4, “Acquisitions and Divestitures”.

(2) Reflects the amount of goodwill that was allocated to the WIS business, which was part of the UBS segment, and was sold on April 1, 2024, as described in Note 4, “Acquisitions and Divestitures”.

Schedule of Finite-Lived Intangible Assets

The components of intangible assets are as follows:


		As of
		September 30, 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	$	792.2	$	—	$	792.2	$	793.0	$	—	$	793.0
Customer relationships	10 - 20	1,466.0		(468.7)		997.3		1,519.9		(464.4)		1,055.5
Distribution agreements	15 and 19	29.2		(27.3)		1.9		29.2		(26.0)		3.2
Trademarks	5 and 12	15.5		(11.2)		4.3		15.5		(9.6)		5.9
Software	7	16.0		(0.5)		15.5		—		—		—
		$	2,318.9	$	(507.7)	$	1,811.2	$	2,357.6	$	(500.0)	$	1,857.6

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

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	$	22.0
2025	85.8
2026	80.4
2027	77.6
2028	75.9
Thereafter	677.3
Total	$	1,019.0

- 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.

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+ Details

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	May 31, 2022
Equity [Abstract]
Stock Repurchase Program, Authorized Amount							$ 1,000.0
Common Stock, Dividends, Per Share, Declared	$ 0.413	$ 0.413	$ 0.413	$ 0.375	$ 0.375	$ 0.375
Dividends, Common Stock	$ 20.2	$ 20.3	$ 20.9	$ 19.1	$ 19.2	$ 19.2
Treasury Stock, Value, Acquired, Cost Method	25.3	303.0	50.5	50.5
Dividends, Preferred Stock	$ 14.4	$ 14.4	$ 14.4	$ 14.4	$ 14.4	$ 14.4
Preferred Stock, Dividends, Per Share, Cash Paid	$ 0.664

ORGANIZATION	9 Months Ended
ORGANIZATION	Sep. 30, 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”).

EMPLOYEE BENEFIT PLANS - Narrative (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
	Feb. 12, 2024	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost		$ 18.8		$ 15.9	$ 58.4	$ 58.8
Pension Cost (Reversal of Cost)		(2.2)		0.0	3.3	0.0
Service cost		0.4		1.2	1.4	3.6
Interest cost		3.2		7.5	13.6	16.4
Expected return on plan assets		(3.2)		(7.4)	(13.3)	(16.4)
Recognized actuarial gain		(0.2)		(0.3)	(0.4)	(0.9)
Net periodic pension (benefit) cost		(2.0)		1.0	4.6	2.7
Pension Cost (Reversal of Cost)		(2.2)		0.0	3.3	0.0
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year		7.0			7.0
Defined Benefit Plan, Plan Assets, Contributions by Employer		1.0			4.4
Pension Cost (Reversal of Cost)		0.0		0.0	0.0	0.0
Service cost		0.4		1.2	1.4	3.6
Interest cost		3.2		2.9	12.5	8.6
Expected return on plan assets		(3.2)		(3.1)	(13.0)	(9.1)
Recognized actuarial gain		(0.2)		(0.3)	(0.4)	(0.9)
Net periodic pension (benefit) cost		0.2		0.7	0.5	2.2
Pension Cost (Reversal of Cost)		0.0		0.0	0.0	0.0
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
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Other Nonoperating Income (Expense)
Pension Cost (Reversal of Cost)		(2.2)		0.0	3.3	0.0
Service cost		0.0		0.0	0.0	0.0
Interest cost		0.0		4.6	1.1	7.8
Expected return on plan assets		0.0		(4.3)	(0.3)	(7.3)
Recognized actuarial gain		0.0		0.0	0.0	0.0
Net periodic pension (benefit) cost		(2.2)		0.3	4.1	0.5
Pension Cost (Reversal of Cost)		(2.2)		0.0	3.3	0.0
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Nonoperating Gains (Losses)		(2.4)		$ (0.2)	3.2	$ (0.9)
WESCODeferredCompensationPlanMember
Defined Benefit Plan Disclosure [Line Items]
Deferred Compensation Liability, Classified, Noncurrent		$ 32.5			$ 32.5		$ 27.4

EARNINGS PER SHARE (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
EARNINGS PER SHARE (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury Stock, Value, Acquired, Cost Method	$ 25.3	$ 303.0	$ 50.5	$ 50.5
Treasury Stock, Common [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury Stock, Shares, Acquired	161,614				2,183,937	325,449
Treasury Stock, Shares, Acquired	161,614				2,183,937	325,449
Treasury Stock, Value, Acquired, Cost Method	$ 25.3				$ 378.8	$ 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				100,000	200,000	200,000

GOODWILL (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
GOODWILL (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Goodwill [Line Items]
Goodwill	$ 3,217.7		$ 3,217.7		$ 3,262.3
Goodwill, Foreign Currency Translation Gain (Loss)			(19.0)
Goodwill, Acquired During Period			32.5
Goodwill, Transfers			(58.1)
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	2,318.9		2,318.9		2,357.6
Finite-Lived Intangible Assets, Accumulated Amortization	(507.7)		(507.7)		(500.0)
Finite-Lived Intangible Assets, Net	1,811.2		1,811.2		1,857.6
Finite-Lived Intangible Asset, Expected Amortization, Year One	22.0		22.0
Finite-Lived Intangible Asset, Expected Amortization, Year Two	85.8		85.8
Finite-Lived Intangible Asset, Expected Amortization, Year Three	80.4		80.4
Finite-Lived Intangible Asset, Expected Amortization, Year Four	77.6		77.6
Finite-Lived Intangible Asset, Expected Amortization, Year Five	75.9		75.9
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	677.3		677.3
Finite-Lived Intangible Asset, Expected Amortization, Total	1,019.0		1,019.0
Amortization of Intangible Assets	21.5	$ 22.1	65.3	$ 66.5
Amortization of Intangible Assets	21.5	$ 22.1	65.3	$ 66.5
Finite-Lived Intangible Asset, Expected Amortization, Year Three	80.4		80.4
Finite-Lived Intangible Asset, Expected Amortization, Year Four	77.6		77.6
Finite-Lived Intangible Asset, Expected Amortization, Year Five	75.9		75.9
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	677.3		677.3
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	15.5		15.5		15.5
Finite-Lived Intangible Assets, Accumulated Amortization	(11.2)		(11.2)		(9.6)
Finite-Lived Intangible Assets, Net	$ 4.3		$ 4.3		5.9
Trademarks [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years		5 years
Trademarks [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	12 years		12 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,466.0		$ 1,466.0		1,519.9
Finite-Lived Intangible Assets, Accumulated Amortization	(468.7)		(468.7)		(464.4)
Finite-Lived Intangible Assets, Net	$ 997.3		$ 997.3		1,055.5
Customer Relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years		10 years
Customer Relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years		20 years
Distribution Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 29.2		$ 29.2		29.2
Finite-Lived Intangible Assets, Accumulated Amortization	(27.3)		(27.3)		(26.0)
Finite-Lived Intangible Assets, Net	$ 1.9		$ 1.9		3.2
Distribution Rights [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years		15 years
Distribution Rights [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	19 years		19 years
Computer Software, Intangible Asset
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	7 years		7 years
Finite-Lived Intangible Assets, Gross	$ 16.0		$ 16.0		0.0
Finite-Lived Intangible Assets, Accumulated Amortization	(0.5)		(0.5)		0.0
Finite-Lived Intangible Assets, Net	15.5		15.5		0.0
EES
Goodwill [Line Items]
Goodwill	829.8		829.8		838.1
Goodwill, Foreign Currency Translation Gain (Loss)			(11.8)
Goodwill, Acquired During Period			3.5
Goodwill, Transfers			0.0
CSS
Goodwill [Line Items]
Goodwill	1,238.8		1,238.8		1,211.6
Goodwill, Foreign Currency Translation Gain (Loss)			(1.8)
Goodwill, Acquired During Period			29.0
Goodwill, Transfers			0.0
UBS
Goodwill [Line Items]
Goodwill	1,149.1		1,149.1		1,212.6
Goodwill, Foreign Currency Translation Gain (Loss)			(5.4)
Goodwill, Acquired During Period			0.0
Goodwill, Transfers			(58.1)
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 792.2		$ 792.2		$ 793.0

REVENUE Variable Consideration (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue, Methods, Inputs, and Assumptions Used [Abstract]
Revenue, Variable Consideration Constraint Increase (Decrease)	$ 110.4	$ 118.4	$ 331.2	$ 333.5

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 706.8	$ 524.1
Accounts Receivable, after Allowance for Credit Loss, Current	3,629.1	3,639.5
Accounts and Other Receivables, Net, Current	398.8	430.5
Inventories, net	3,630.1	3,572.1
Prepaid expenses and other current assets	318.7	225.4
Assets, Current	8,683.5	8,391.6
Property, buildings and equipment, net of accumulated depreciation of $229,041 and $213,758 in 2014 and 2013, respectively	441.7	423.6
Operating Lease, Right-of-Use Asset	747.6	761.2
Intangible assets, net	1,811.2	1,857.6
Goodwill	3,217.7	3,262.3
Deferred Income Tax Assets, Net	38.1	42.3
Other assets	335.2	322.3
Assets	15,275.0	15,060.9
Accounts payable	2,839.1	2,431.5
Accrued payroll and benefit costs	219.9	191.7
Current portion of long-term debt	14.9	8.6
Other Liabilities, Current	854.6	756.6
Liabilities, Current	3,928.5	3,388.4
Total long-term debt	5,007.8	5,313.1
Operating Lease, Liability, Noncurrent	624.6	641.7
Deferred Income Tax Liabilities, Net	440.4	451.9
Other Liabilities, Noncurrent	236.9	233.9
Liabilities	10,238.2	10,029.0
Commitments and Contingencies
Additional capital	2,042.4	2,037.1
Retained earnings	4,829.8	4,391.7
Treasury stock, at cost; 24,913,926 and 22,720,986 shares in 2024 and 2023, respectively	(1,440.7)	(1,060.4)
Accumulated other comprehensive income	(389.8)	(332.0)
Total WESCO International, Inc. stockholders’ equity	5,042.4	5,037.1
Noncontrolling interest	(5.6)	(5.2)
Total stockholders’ equity	5,036.8	5,031.9
Liabilities and Equity	15,275.0	15,060.9
Preferred Stock
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0.0	0.0
Series A Preferred Stock
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0.0	0.0
Common Stock
Common stock	0.7	0.7
Common Class B
Common stock	$ 0.0	$ 0.0

Summary of Non-Qualified Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 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	773,494		773,494		818,284
Granted (in shares)			0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised			(44,063)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures			(727)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	773,494		773,494
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 59.37		$ 59.37		$ 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)			62.58
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)			76.25
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 59.37		$ 59.37
Weighted Average Remaining Contractual Term, Outstanding (in years)			4 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 84.0		$ 84.0
Weighted Average Remaining Contractual Term, Exercisable (in years)			4 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 84.0		$ 84.0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 4.7
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	239,111		239,111		163,082
Granted (in shares)	0	1,593	85,425	78,729
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised			(3,053)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures			(6,343)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	79,145		79,145
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 147.23		$ 147.23		$ 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)			154.71
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 136.93		$ 136.93
Weighted Average Remaining Contractual Term, Outstanding (in years)			8 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 5.2		$ 5.2
Weighted Average Remaining Contractual Term, Exercisable (in years)			7 years 8 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 2.5		$ 2.5

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	9 Months Ended
	Sep. 30, 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	773,494	818,284
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 59.37	$ 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	(44,063)
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	$ 62.58
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	(727)
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	$ 76.25
Weighted Average Remaining Contractual Term, Outstanding (in years)	4 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 84.0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	773,494
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 59.37
Weighted Average Remaining Contractual Term, Exercisable (in years)	4 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 84.0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 4.7

SCHEDULE OF DEBT (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Finance lease obligations	$ 58.2	$ 31.4
Total debt	5,068.5	5,359.0
Fair value adjustment to the Anixter Notes	0.1	0.1
Unamortized debt issuance costs	(45.9)	(37.4)
Short-term debt and current portion of long-term debt	(14.9)	(8.6)
Total long-term debt	5,007.8	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	1,450.0	1,550.0
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Debt	485.0	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	0.0
7.250% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term Debt	1,320.3	1,319.4
Debt Instrument, Unamortized Discount	$ 4.7	5.6
6.375% Senior Notes due 2029
Debt Instrument [Line Items]
Long-term Debt		0.0
6.625% Senior Notes due 2032
Debt Instrument [Line Items]
Long-term Debt		$ 0.0

EARNINGS PER SHARE

9 Months Ended

Sep. 30, 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				Nine Months Ended
	September 30				September 30
(In millions, except per share data)	2024		2023		2024		2023
Net income attributable to WESCO International, Inc.	$	204.3	$	233.4	$	552.2	$	623.6
Less: Preferred stock dividends	14.4		14.4		43.1		43.1
Net income attributable to common stockholders	$	189.9	$	219.0	$	509.1	$	580.5
Weighted-average common shares outstanding used in computing basic earnings per share	49.1		51.2		50.0		51.2
Common shares issuable upon exercise of dilutive equity awards	0.7		1.0		0.8		1.2
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share	49.8		52.2		50.8		52.4
Earnings per share attributable to common stockholders
Basic	$	3.87	$	4.28	$	10.18	$	11.34
Diluted	$	3.81	$	4.20	$	10.02	$	11.08

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 and nine months ended September 30, 2024, there were approximately 0.2 million antidilutive shares. For the three and nine months ended September 30, 2023, there were approximately 0.1 million and 0.2 million antidilutive shares, respectively.

INCOME TAXES Income Tax Rates (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	25.30%	15.90%	25.40%	20.40%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent		1080.00%	120.00%	660.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount		$ 7.6	$ 8.6

DEBT (Tables)

9 Months Ended

Sep. 30, 2024

Debt Disclosure [Abstract]

Schedule of Debt

The following table sets forth Wesco's outstanding indebtedness:


	As of
	September 30, 2024		December 31, 2023
	(In millions)
International lines of credit	$	0.8	$	1.0
Accounts Receivable Securitization Facility	1,450.0		1,550.0
Revolving Credit Facility	485.0		953.0
6.00% Anixter Senior Notes due 2025	4.2		4.2
7.125% Senior Notes due 2025	—		1,500.0
7.250% Senior Notes due 2028, less debt discount of $4.7 and $5.6 in 2024 and 2023, respectively	1,320.3		1,319.4
6.375% Senior Notes due 2029	900.0		—
6.625% Senior Notes due 2032	850.0		—
Finance lease obligations	58.2		31.4
Total debt	5,068.5		5,359.0
Plus: Fair value adjustments to the Anixter Senior Notes	0.1		0.1
Less: Unamortized debt issuance costs	(45.9)		(37.4)
Less: Short-term debt and current portion of long-term debt	(14.9)		(8.6)
Total long-term debt	$	5,007.8	$	5,313.1

SCHEDULE OF SHARE-BASED PAYMENT AWARD, VALUATION ASSUMPTIONS (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2023 Rate	Sep. 30, 2024 Rate	Sep. 30, 2023 Rate
Share-Based Payment Arrangement [Abstract]
WESCO expected volatility	52.00%	55.00%	50.00%
Risk free interest rate	4.40%	4.20%	4.10%
Expected life (in years)	5 years	5 years	5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.96%	1.09%	0.89%

SUMMARY OF RESTRICTED STOCK UNITS (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based awards outstanding (in shares)	426,111		426,111		407,613
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 148.54		$ 148.54		$ 127.49
Granted (in shares)	1,942	1,649	240,233	175,513
Granted, Weighted Average Fair Value (in dollars per share)	$ 150.44	$ 140.91	$ 157.13	$ 170.13
Vested (in shares)			(193,762)
Vested in Period, Weighted Average Fair Value (in dollars per share)			$ 115.40
Forfeited (in shares)			(27,973)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value			$ 142.78

ACCOUNTING POLICIES	9 Months Ended
ACCOUNTING POLICIES	Sep. 30, 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 September 30, 2024, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Stockholders’ Equity for the three and nine months ended September 30, 2024 and 2023, and the unaudited Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 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. Reclassifications The Consolidated Statement of Cash Flows for the nine months ended September 30, 2023, includes certain reclassifications to previously reported amounts to conform to the current period's presentation. Such reclassifications had no impact on the totals of operating, investing and financing cash flow activities. 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 September 30, 2024 and December 31, 2023, the amounts due to suppliers that participate in the Company’s supplier finance programs were approximately $21.3 million and $32.6 million, respectively, which are included in accounts payable in the Condensed Consolidated Balance Sheets. Loss on Abandonment of Assets During the second quarter of 2024, management determined that a third-party developed operations management software product would be abandoned in favor of an application that better suits the Company's operations and the Company recognized a $17.8 million loss on abandonment of assets, which is recorded as a component of selling, general and administrative expenses in the Condensed Consolidated Statement of Income. 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 programs, as described above. 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 material to Wesco’s financial position, results of operations or cash flows.
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 September 30, 2024 and December 31, 2023, the amounts due to suppliers that participate in the Company’s supplier finance programs were approximately $21.3 million and $32.6 million, respectively, which are included in accounts payable in the Condensed Consolidated Balance Sheets.

EARNINGS PER SHARE (Tables)

9 Months Ended

Sep. 30, 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				Nine Months Ended
	September 30				September 30
(In millions, except per share data)	2024		2023		2024		2023
Net income attributable to WESCO International, Inc.	$	204.3	$	233.4	$	552.2	$	623.6
Less: Preferred stock dividends	14.4		14.4		43.1		43.1
Net income attributable to common stockholders	$	189.9	$	219.0	$	509.1	$	580.5
Weighted-average common shares outstanding used in computing basic earnings per share	49.1		51.2		50.0		51.2
Common shares issuable upon exercise of dilutive equity awards	0.7		1.0		0.8		1.2
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share	49.8		52.2		50.8		52.4
Earnings per share attributable to common stockholders
Basic	$	3.87	$	4.28	$	10.18	$	11.34
Diluted	$	3.81	$	4.20	$	10.02	$	11.08

Segment Reporting

9 Months Ended

Sep. 30, 2024

Segment Reporting [Abstract]

Segment Reporting Disclosure

14. 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 certain 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 table sets forth net sales by reportable segment for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	2,151.2	$	2,190.7	$	6,423.1	$	6,526.1
CSS	1,955.1		1,778.0		5,491.1		5,360.9
UBS	1,383.1		1,675.7		4,404.9		5,024.8
Total	$	5,489.4	$	5,644.4	$	16,319.1	$	16,911.8

The following table sets forth adjusted EBITDA and adjusted EBITDA margin % by reportable segment for the periods presented:


	Three Months Ended September 30						Nine Months Ended September 30
(In millions)	2024			2023			2024			2023
EES	$	186.3		$	191.5		$	547.0		$	563.5
Adjusted EBITDA Margin	8.7		%	8.7		%	8.5		%	8.6		%
CSS	$	175.2		$	175.5		$	453.2		$	510.5
Adjusted EBITDA Margin	9.0		%	9.9		%	8.3		%	9.5		%
UBS	$	156.5		$	196.4		$	499.4		$	572.7
Adjusted EBITDA Margin	11.3		%	11.7		%	11.3		%	11.4		%

The following table sets forth depreciation and amortization by reportable segment for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	12.2	$	10.9	$	34.8	$	32.3
CSS	17.6		18.0		53.9		53.9
UBS	6.9		6.3		21.3		18.7
Corporate	9.3		9.9		27.6		31.5
Total	$	46.0	$	45.1	$	137.6	$	136.4


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
EES	$	5.6	$	1.7	$	14.3	$	12.0
CSS	4.7		9.7		39.4		38.2
UBS	(19.7)		0.6		(122.1)		(0.5)
Corporate	(15.5)		(8.3)		(30.9)		(35.1)
Total	$	(24.9)	$	3.7	$	(99.3)	$	14.6

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


	As of
(In millions)	September 30, 2024		December 31, 2023
EES	$	4,648.2	$	4,553.6
CSS	5,830.7		5,626.6
UBS	3,671.1		3,908.5
Corporate(1)	1,125.0		972.2
Total	$	15,275.0	$	15,060.9

The following table reconciles adjusted EBITDA by segment to income before income taxes, for the periods presented:


	Three Months Ended September 30				Nine Months Ended September 30
(In millions)	2024		2023		2024		2023
Adjusted EBITDA by segment
EES	$	186.3	$	191.5	$	547.0	$	563.5
CSS	175.2		175.5		453.2		510.5
UBS	156.5		196.4		499.4		572.7
Total segment adjusted EBITDA	518.0		563.4		1,499.6		1,646.7
Less:
Corporate expenses not allocated to segments	132.9		134.9		429.3		409.6
Interest expense, net	86.5		98.5		279.8		292.3
Depreciation and amortization	46.0		45.1		137.6		136.4
Other (income) expense, net	(24.9)		3.7		(99.3)		14.6
Stock-based compensation expense allocated to segments	3.5		2.9		10.6		10.0
Income before income taxes	$	274.0	$	278.3	$	741.6	$	783.8

Note: Adjusted EBITDA and Adjusted EBITDA margin % provide indicators of the Company’s performance and its ability to meet debt service requirements. Adjusted EBITDA is defined as earnings before interest, taxes, depreciation and amortization before other non-operating expenses (income) and non-cash stock-based compensation expense. Adjusted EBITDA margin % is calculated by dividing Adjusted EBITDA by net sales.

- 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.

+ References

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+ Details

ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Supplier Finance Program, Obligation	$ 21.3						$ 21.3		$ 32.6
Dividends, Preferred Stock	14.4	$ 14.4	$ 14.4	$ 14.4	$ 14.4	$ 14.4
Dividends, Common Stock	(20.2)	$ (20.3)	$ (20.9)	(19.1)	$ (19.2)	$ (19.2)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 706.8			$ 631.4			706.8	$ 631.4	$ 524.1	$ 527.3
Assets Disposed of by Method Other than Sale, in Period of Disposition, Gain (Loss) on Disposition							$ 17.8	$ 0.0

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating Activities:
Net income	$ 553,500	$ 623,600
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	137,600	136,400
Stock-based compensation expense	19,600	34,700
Amortization of Debt Issuance Costs and Discounts	12,200	11,100
Gain (Loss) on Disposition of Business	122,200	0
Assets Disposed of by Method Other than Sale, in Period of Disposition, Gain (Loss) on Disposition	17,800	0
Other operating activities, net	1,300	7,900
Changes in assets and liabilities
Increase (Decrease) in Accounts Receivable	217,900	133,400
Increase (Decrease) in Accounts and Other Receivables	28,100	18,700
Inventories, net	(85,000)	(62,700)
Increase (Decrease) in Other Operating Assets	(127,700)	(51,800)
Accounts payable	478,000	(86,500)
Accrued payroll and benefit costs	26,100	(120,900)
Other current and noncurrent liabilities	103,200	46,800
Net cash provided by operating activities	824,600	423,900
Investing Activities:
Capital expenditures	(70,400)	(63,600)
Cash paid for acquisition	(41,700)	0
Proceeds from Divestiture of Businesses, Net of Cash Divested	354,900	0
Other investing activities	6,900	2,400
Net cash used in investing activities	249,700	(61,200)
Financing Activities:
Proceeds from (Repayments of) Short-term Debt	200	1,300
Proceeds from issuance of long-term debt	5,524,000	2,114,200
Repayments of Other Long-term Debt	5,842,400	2,156,500
Payments of Debt Issuance Costs	(26,600)	0
Payments for Repurchase of Common Stock	(26,200)	(68,000)
Payments for Repurchase of Common Stock	(375,000)	(50,000)
Payments of Ordinary Dividends, Common Stock	(61,400)	(57,600)
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	43,100	43,100
Other financing activities, net	(23,800)	6,300
Net cash used in financing activities	(874,300)	(253,400)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations	(17,300)	(5,200)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	182,700	104,100
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	706,800	631,400
Supplemental Cash Flow Information [Abstract]
Interest Paid, Excluding Capitalized Interest, Operating Activities	251,400	235,000
Income Taxes Paid	223,000	165,000
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 161,900	$ 186,100

Business Combinations, Asset Acquisitions, and Joint Venture Formation	9 Months Ended
	Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Business Combination Disclosure	Independent Electric Supply Inc. Effective July 1, 2024, the Company acquired the assets and liabilities of Independent Electric Supply Inc. (“IES”), a full-line electrical distributor headquartered in Ontario, Canada. The total preliminary estimated fair value of consideration for the acquisition of IES of $13.2 million includes total cash consideration of $11.6 million, net of cash acquired, paid at closing with cash on hand, and contingent consideration not to exceed $2.9 million. The assets acquired included a customer relationship intangible asset with an estimated fair value of $5.9 million. entroCIM On June 3, 2024, the Company acquired the assets and liabilities held by Warez, LLC and Hepta Systems, LLC, which own and operate the entroCIM business (collectively, “entroCIM”). entroCIM is an innovator in data center and building intelligence software. The total preliminary estimated fair value of consideration for the acquisition of entroCIM of $36.5 million includes total cash consideration of $30.1 million, paid at closing with cash on hand, and contingent consideration not to exceed $8.0 million, with an estimated fair value of $6.4 million, recorded in current and noncurrent liabilities in the Condensed Consolidated Balance Sheet as of September 30, 2024. The preliminary purchase consideration was allocated to the identified assets acquired and liabilities assumed based on their respective acquisition date fair value, which primarily comprised a developed software intangible asset with an estimated fair value of $8.0 million based on an income valuation method, with the excess of $29.0 million allocated to goodwill in the Company's CSS reportable segment.
Acquisitions	Wesco Integrated Supply (“WIS”) Divestiture On April 1, 2024, Wesco Distribution, Inc. (“Wesco Distribution”) completed the sale of its WIS business for total consideration of $334.2 million, adjusted from the base purchase price of $350.0 million for estimated net working capital, estimated closing cash, and estimated closing indebtedness. The WIS business, located primarily in the U.S. and Canada, was part of the UBS reportable segment and provided products and services to large industrial and commercial end-users to support their maintenance, repair, and operating spend. During the third quarter, the Company finalized the net working capital, closing cash, and closing indebtedness purchase price adjustments, which resulted in a working capital adjustment of $20.7 million and an increase to the gain from the sale. The Company recognized a gain from the sale of $19.3 million and $122.2 million for the three and nine months ended September 30, 2024, respectively, which is recorded as a component of other (income) expense, net in the Condensed Consolidated Statements of Income and Comprehensive Income. 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. Revenues associated with these TSAs are not material. The sale of the WIS business did not represent a strategic shift that had a major effect on the Company’s operations and financial results, and therefore does not meet the criteria to be classified as discontinued operations.

COMMITMENTS AND CONTINGENCIES	9 Months Ended
COMMITMENTS AND CONTINGENCIES	Sep. 30, 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. 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.

GOODWILL (Notes)

9 Months Ended

Sep. 30, 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:


	Nine Months Ended
	September 30, 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	(11.8)		(1.8)		(5.4)		(19.0)
Adjustments to goodwill for acquisitions(1)	3.5		29.0		—		32.5
Adjustment to goodwill for divestiture(2)	—		—		(58.1)		(58.1)
Ending balance, September 30	$	829.8	$	1,238.8	$	1,149.1	$	3,217.7

The components of intangible assets are as follows:


		As of
		September 30, 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	$	792.2	$	—	$	792.2	$	793.0	$	—	$	793.0
Customer relationships	10 - 20	1,466.0		(468.7)		997.3		1,519.9		(464.4)		1,055.5
Distribution agreements	15 and 19	29.2		(27.3)		1.9		29.2		(26.0)		3.2
Trademarks	5 and 12	15.5		(11.2)		4.3		15.5		(9.6)		5.9
Software	7	16.0		(0.5)		15.5		—		—		—
		$	2,318.9	$	(507.7)	$	1,811.2	$	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 $21.5 million and $22.1 million for the three months ended September 30, 2024 and 2023, respectively, and $65.3 million and $66.5 million for the nine months ended September 30, 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	$	22.0
2025	85.8
2026	80.4
2027	77.6
2028	75.9
Thereafter	677.3
Total	$	1,019.0