CONCENTRATIONS OF CREDIT RISK AND SIGNIFICANT SUPPLIERS	12 Months Ended
Dec. 31, 2019
Risks and Uncertainties [Abstract]
CONCENTRATIONS OF CREDIT RISK AND SIGNIFICANT SUPPLIERS	6. CONCENTRATIONS OF CREDIT RISK AND SIGNIFICANT SUPPLIERS WESCO distributes its products and services and extends credit to a large number of customers in the industrial, construction, utility, and commercial, institutional and government markets. Based upon WESCO’s broad customer base, Managment has concluded that it has no material credit risk as a result of customer concentration. WESCO is subject to supplier concentration risk as Eaton Corporation, the Company's largest supplier, accounted for approximately 11% of its purchases in 2019, 2018 and 2017.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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