v3.26.1
STOCK-BASED COMPENSATION (Tables)
 6 Months Ended
Jun. 30, 2026
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 six months ended June 30, 2026 and 2025, Wesco granted the following stock options, restricted stock units, and performance-based awards at the following weighted-average fair values:
Three Months EndedSix Months Ended
June 30,
2026		June 30,
2025		June 30,
2026		June 30,
2025
Stock options granted— 4,745 58,729 89,221 
Weighted-average fair valuen/a$79.03 $124.11 $76.72 
Restricted stock units granted3,853 7,144 143,165 222,747 
Weighted-average fair value$348.82 $164.30 $297.35 $179.33 
Performance-based awards granted747 4,562 49,187 76,864 
Weighted-average fair value$396.45 $194.03 $322.68 $191.86 
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 six months ended June 30, 2026:
AwardsWeighted-
Average
Exercise
Price		Weighted-
Average
Remaining
Contractual Term (In years)		Aggregate
Intrinsic
Value
(In millions)
Outstanding at December 31, 2025
411,759 $59.12   
     Granted— —   
     Exercised(254,849)54.59  
     Forfeited(389)42.44   
Outstanding at June 30, 2026
156,521 $66.53 3.3$43.7 
Exercisable at June 30, 2026
156,521 $66.53 3.3$43.7 
For the six months ended June 30, 2026, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $71.4 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 six months ended June 30, 2026:
AwardsWeighted-
Average
Fair
Value
Unvested at December 31, 2025
457,943 $165.89 
     Granted143,165 297.35 
     Vested(159,551)167.85 
     Forfeited(8,633)214.92 
Unvested at June 30, 2026
432,924 $207.84 
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 six months ended June 30, 2026:
AwardsWeighted-
Average
Fair
Value
Unvested at December 31, 2025
194,635 $171.72 
     Granted49,187 322.68 
     Vested— — 
     Forfeited(59,240)172.22 
Unvested at June 30, 2026
184,582 $211.47 
Share-Based Payment Arrangement, Option, Activity
The following table sets forth a summary of stock options and related information for the six months ended June 30, 2026:
AwardsWeighted-
Average
Exercise
Price		Weighted-
Average
Remaining
Contractual Term (In years)		Aggregate
Intrinsic
Value
(In millions)
Outstanding at December 31, 2025
285,935 $156.62   
     Granted58,729 295.31   
     Exercised(20,125)152.17  
     Forfeited(1,029)222.29   
Outstanding at June 30, 2026
323,510 $181.87 7.7$52.9 
Exercisable at June 30, 2026
190,441 $151.06 6.8$37.0 
For the six months ended June 30, 2026, the aggregate intrinsic value of stock options exercised during such period was $3.8 million.
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 EndedSix Months Ended
June 30,
2026		June 30,
2025		June 30,
2026		June 30,
2025
Risk free interest raten/a4.0%3.6%4.1%
Expected life (in years)n/a555
Expected volatilityn/a47%45%47%
Expected dividend yieldn/a0.98 %0.68%1.01%