WESCO International (WCC) 10-Q 4 May 15 2015 Q1 Quarterly report Financial data

DOCUMENT_AND_ENTITY_INFORMATIO

DOCUMENT AND ENTITY INFORMATION Document	3 Months Ended
	Mar. 31, 2015	1-May-15
Entity [Abstract]
Entity Registrant Name	WESCO INTERNATIONAL INC.
Entity Central Index Key	929008
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		44,217,532

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Other Accrued Liabilities, Current	$175,389	$181,672
Current Assets:
Cash and cash equivalents	154,351	128,319
Allowance for Doubtful Accounts Receivable, Current	20,646	21,084
Trade accounts receivable, net of allowance for doubtful accounts of $23,069 and $19,309 in 2014 and 2013, respectively	1,082,199	1,117,420
Accounts and Other Receivables, Net, Current	123,896	138,745
Inventories, net	814,363	819,502
Prepaid expenses and other current assets	138,652	146,352
Total current assets	2,313,461	2,350,338
Property, buildings and equipment, net of accumulated depreciation of $229,041 and $213,758 in 2014 and 2013, respectively	173,878	182,725
Intangible assets, net	398,673	429,840
Goodwill	1,675,581	1,735,440
Other assets	50,787	56,094
Total assets	4,612,380	4,754,437
Current Liabilities:
Accounts payable	771,881	765,135
Accrued payroll and benefit costs	39,948	67,935
Short-term debt	49,663	46,787
Current portion of long-term debt	2,231	2,343
Total current liabilities	1,039,112	1,063,872
Long-term Debt, Excluding Current Maturities	1,336,881	1,366,430
Other noncurrent liabilities	49,387	49,227
Deferred income taxes	349,682	346,743
Total liabilities	2,775,062	2,826,272
Commitments and Contingencies
Stockholders' Equity:
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0	0
Additional capital	1,100,068	1,102,369
Retained earnings	1,690,808	1,643,914
Treasury stock, at cost; 18,247,467 and 18,179,275 shares in 2014 and 2013, respectively	-637,755	-616,366
Accumulated other comprehensive income	-315,706	-201,892
Total WESCO International stockholders' equity	1,837,318	1,928,165
Noncontrolling interest	-725	-487
Total stockholders' equity	1,838,043	1,928,652
Total liabilities and stockholders' equity	4,612,380	4,754,437
Common Stock [Member]
Stockholders' Equity:
Common stock	585	584
Common Class B [Member]
Stockholders' Equity:
Common stock	$43	$43

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parentheticals) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts	$20,646,000	$21,084,000
Accumulated depreciation	232,412,000	229,196,000
Finite-Lived Intangible Assets, Accumulated Amortization	139,192	110,828
Debt discount	$171,547,000	$174,686,000
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Treasury stock, shares (in shares)	18,550,758	18,250,178
Common Stock [Member]
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized (in shares)	210,000,000	210,000,000
Common stock, shares, issued (in shares)	58,480,990	58,400,736
Common stock, shares outstanding (in shares)	44,269,663	44,489,989
Common Class B [Member]
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares, issued (in shares)	4,339,431	4,339,431
Common stock, shares outstanding (in shares)	0	0

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Net sales	$1,816,330	$1,810,825
Cost of goods sold	1,448,639	1,436,032
Selling, general and administrative expense	264,585	265,462
Depreciation and amortization	15,921	16,372
Income from operations	87,185	92,959
Interest expense, net	20,894	20,688
Income before income taxes	66,291	72,271
Provision for income taxes	19,498	20,416
Net income	46,793	51,855
Net (loss) income attributable to noncontrolling interest	-238	-50
Net income attributable to WESCO International, Inc.	47,031	51,905
Comprehensive Income:
Foreign currency translation adjustment	-113,814	-46,500
Comprehensive income attributable to WESCO International, Inc.	($66,783)	$5,405
Earnings per share attributable to WESCO International, Inc.
Basic (in dollars per share)	$1.06	$1.17
Diluted (in dollars per share)	$0.90	$0.97

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Operating Activities:
Net income	$46,793	$51,855
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	15,921	16,372
Deferred income taxes	7,849	7,864
Other operating activities, net	7,665	2,202
Changes in assets and liabilities
Increase (Decrease) in Accounts Receivable	-9,705	55,285
Increase (Decrease) in Accounts and Other Receivables	-12,075	-22,868
Inventories, net	-13,248	-17,373
Prepaid expenses and other current assets	21,474	-19,668
Accounts payable	20,589	43,604
Accrued payroll and benefit costs	-26,635	-16,854
Other current and noncurrent liabilities	-12,132	11,128
Net cash provided by operating activities	90,056	46,713
Investing Activities:
Capital expenditures	-5,026	-5,012
Acquisition payments, net of cash acquired	0	-91,187
Other investing activities	785	39
Net cash used in investing activities	-4,241	-96,160
Financing Activities:
Proceeds from issuance of short-term debt	49,360	18,503
Repayments of short-term debt	-43,958	-13,211
Proceeds from issuance of long-term debt	319,939	404,922
Repayments of Long-term Debt	-344,321	-390,232
Other financing activities, net	-7,209	8,888
Net cash used in financing activities	-53,791	23,539
Payments for Repurchase of Common Stock	-27,602	-5,331
Effect of exchange rate on cash and cash equivalents	-5,992	-1,461
Net change in cash and cash equivalents	26,032	-27,369
Cash and cash equivalents at the beginning of period	128,319	123,725
Cash and cash equivalents at the end of period	$154,351	$96,356

ORGANIZATION

ORGANIZATION	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION	ORGANIZATION
	WESCO International, Inc. and its subsidiaries (collectively, “WESCO” or the "Company"), headquartered in Pittsburgh, Pennsylvania, is a full-line distributor of electrical, industrial and communications maintenance, repair and operating (“MRO”) and original equipment manufactures (“OEM”) products, construction materials, and advanced supply chain management and logistics services used primarily in the industrial, construction, utility and commercial, institutional and government markets. We serve over 75,000 active customers globally, through approximately 485 full service branches and nine distribution centers located primarily in the United States, Canada and Mexico, with operations in 16 additional countries.

ACCOUNTING_POLICIES

ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
ACCOUNTING POLICIES	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’s 2014 Annual Report on Form 10-K as filed with the SEC on February 24, 2015. The Condensed Consolidated Balance Sheet at December 31, 2014 was derived from the audited Consolidated Financial Statements as of that date, but does not include all of the disclosures required by accounting principles generally accepted in the United States of America.
	The unaudited Condensed Consolidated Balance Sheet as of March 31, 2015, the unaudited Condensed Consolidated Statements of Comprehensive Income (Loss) for the three months ended March 31, 2015 and 2014, respectively, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2015 and 2014, 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.
	The Condensed Consolidated Balance Sheet at December 31, 2014 and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2014 include certain reclassifications to previously reported amounts to conform to the current period presentation.
	Fair Value of Financial Instruments
	The Company measures the fair value of financial assets and liabilities in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 820, "Fair Value Measurements and Disclosures," which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements.
	ASC 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows:
	•	Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date.
	•	Level 2 inputs include inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities.
	•	Level 3 inputs are unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.
	At March 31, 2015, the carrying value of WESCO’s 6.0% Convertible Senior Debentures due 2029 (the "2029 Debentures") was $178.6 million and the fair value was approximately $849.8 million. At December 31, 2014, the carrying value of WESCO’s 2029 Debentures was $177.6 million and the fair value was approximately $936.1 million. The reported carrying amounts of WESCO’s other debt instruments approximate their fair values. The Company uses a market approach to fair value all of its debt instruments, utilizing quoted prices in active markets, interest rates and other relevant information generated by market transactions involving similar instruments. Therefore, all of the Company's debt instruments are classified as Level 2 within the valuation hierarchy. For all of the Company's remaining financial instruments, consisting of cash and cash equivalents, accounts receivable, accounts payable and other accrued liabilities, carrying values are considered to approximate fair value due to the short maturity of these instruments.
	New Accounting Pronouncements
	In May 2014, the FASB and International Accounting Standards Board issued a converged final standard on the recognition of revenue from contracts with customers. This updated guidance provides a framework for addressing revenue recognition issues and replaces almost all existing revenue recognition guidance in current U.S. generally accepted accounting principles. The core principle of the new standard is for companies to recognize revenue to depict the transfer of goods or services to customers in amounts that reflect the consideration to which the company expects to be entitled in exchange for those goods or services. The new standard will also result in enhanced disclosures about revenue, provide guidance for transactions that were not previously addressed comprehensively, and improve guidance for multiple-element arrangements. This guidance is effective for interim and annual periods beginning after December 15, 2016. Management is currently evaluating the future impact of this guidance on WESCO's financial position, results of operations and cash flows.
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The amendments in this Update require a reporting entity to treat a performance target that affects vesting and could be achieved after the requisite service period as a performance condition. A reporting entity should apply FASB ASC Topic 718, Compensation—Stock Compensation, to awards with performance conditions that affect vesting. For all entities, ASU 2014-12 is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. This ASU may be adopted either prospectively for share-based payment awards granted or modified on or after the effective date, or retrospectively, using a modified retrospective approach. The modified retrospective approach would apply to share-based payment awards outstanding as of the beginning of the earliest annual period presented in the financial statements on adoption and to all new or modified awards thereafter. The adoption of this guidance is not expected to have an impact on WESCO's consolidated financial statements and notes thereto.
	In September 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. This ASU describes how an entity should assess its ability to meet obligations and sets disclosure requirements for how this information should be disclosed in the financial statements. The standard provides accounting guidance that will be used with existing auditing standards. The amendments in this ASU are effective for the annual period ending after December 15, 2016 and for annual periods and interim periods thereafter. Early application is permitted. The adoption of this guidance is not expected to have an impact on WESCO's consolidated financial statements and notes thereto.
	In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs. To simplify the presentation of debt issuance costs, the amendments in this Update require that debt issuance costs related to a recognized liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this Update. For public business entities, this ASU is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within fiscal years beginning after December 15, 2016. Early adoption is permitted for financial statements that have not been previously issued. An entity should apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. Upon transition, an entity is required to comply with the applicable disclosures for a change in an accounting principle. These disclosures include the nature of and reason for the change in accounting principle, the transition method, a description of the prior-period information that has been retrospectively adjusted, and the effect of the change on the financial statement line items (that is, debt issuance cost asset and the debt liability). Management is currently evaluating the future impact of this guidance on WESCO's financial position, results of operations and cash flows.

ACQUISITIONS

ACQUISITIONS	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS
	The following table sets forth the consideration paid for acquisitions during the three months ended March 31, 2014:
	(In thousands of dollars)
	Fair value of assets acquired	$	104,601
	Fair value of liabilities assumed	13,414
	Cash paid for acquisitions	$	91,187
	2014 Acquisitions of LaPrairie, Inc., Hazmasters, Inc. and Hi-Line Utility Supply.
	On February 1, 2014, WESCO Distribution, Inc., through its wholly-owned Canadian subsidiary, completed the acquisition of LaPrairie, Inc. ("LaPrairie"), a wholesale distributor of electrical products with approximately $30 million in annual sales servicing the transmission, distribution, and substation needs of utilities and utility contractors from a single location in Newmarket, Ontario. WESCO funded the purchase price paid at closing with cash. The purchase price was allocated to the respective assets and liabilities based upon their estimated fair values as of the acquisition date. The fair value of intangibles was estimated by management and the allocation resulted in intangible assets of $11.0 million and goodwill of $8.9 million. The majority of goodwill is deductible for tax purposes.
	On March 17, 2014, WESCO Distribution, Inc., through its wholly-owned Canadian subsidiary, completed the acquisition of Hazmasters, Inc. ("Hazmasters"), a leading independent Canadian distributor of safety products with approximately $80 million in annual sales servicing customers in the industrial, construction, commercial, institution, and government markets from 14 branches across Canada. WESCO funded the purchase price paid at closing with cash and borrowings under the Revolving Credit Facility. The purchase price was allocated to the respective assets and liabilities based upon their estimated fair values as of the acquisition date. The fair value of intangibles was estimated by management and the allocation resulted in intangible assets of $28.1 million and goodwill of $29.5 million, which is not deductible for tax purposes.
	On June 11, 2014, Wesco Distribution, Inc., completed the acquisition of Hi-Line Utility Supply ("Hi-Line"), a provider of utility MRO and safety products, as well as rubber goods testing and certification services, with approximately $30 million in annual sales from locations in Chicago, Illinois and Millbury, Massachusetts. WESCO funded the purchase price paid at closing with cash. The purchase price was allocated to the respective assets and liabilities based upon their estimated fair values as of the acquisition date. The fair value of intangibles was estimated by management and the allocation resulted in intangible assets of $14.2 million and goodwill of $24.0 million. The majority of goodwill is deductible for tax purposes.
	For all acquisitions made in 2014, the intangible assets include customer relationships of $38.9 million amortized over 2 to 12 years, supplier relationships of $3.2 million amortized over 10 years, trademarks of $10.9 million, and other intangibles of $0.3 million. Certain trademarks have been assigned an indefinite life while others are amortized over 5 and 10 years. No residual value is estimated for the intangible assets being amortized.

STOCKBASED_COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION
	WESCO’s stock-based employee compensation plans are comprised of 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-settled stock appreciation rights and performance-based awards with market conditions is determined using the Black-Scholes and Monte Carlo simulation models, respectively. 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 employee behavior that is reviewed on an annual basis. No dividends are assumed.
	During the three months ended March 31, 2015 and 2014, WESCO granted the following stock-settled appreciation rights, restricted stock units and performance-based awards at the following weighted-average fair values and assumptions:
		Three Months Ended
		March 31,				March 31,
		2015				2014
	Stock-settled appreciation rights granted	394,182				272,213
	Weighted-average fair value	$	21.68			$	30.66
	Restricted stock units granted	78,292				62,506
	Weighted-average fair value	$	69.54			$	85.35
	Performance-based awards granted	59,661				44,046
	Weighted-average fair value	$	67.81			$	86.65
	The fair value of stock-settled appreciation rights was estimated using the following weighted-average assumptions:
		Three Months Ended
		March 31,			March 31,
		2015			2014
	Risk free interest rate	1.6	%		1.5	%
	Expected life (in years)	5			5
	Expected volatility	32	%		39	%
	The risk-free interest rate is based on the U.S. Treasury Daily Yield Curve rates as of the grant date. The expected life is based on historical exercise experience and the expected volatility is based on the volatility of the Company's daily stock prices over a five-year period preceding the grant date.
	The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2015:
		Awards			Weighted-			Weighted-	Aggregate
					Average			Average	Intrinsic
					Exercise			Remaining	Value
					Price			Contractual Term (In years)	(In thousands)
	Outstanding at December 31, 2014	2,480,745			$	50.91
	Granted	394,182			69.54
	Exercised	(27,316	)		40.78
	Forfeited	(7,800	)		81.12
	Outstanding at March 31, 2015	2,839,811			53.51			5.6	$	51,128.90
	Exercisable at March 31, 2015	2,190,049			$	47.4		4.5	$	50,956.50
	The following table sets forth a summary of time-based restricted stock units and related information for the three months ended March 31, 2015:
		Awards			Weighted-
					Average
					Fair
					Value
	Unvested at December 31, 2014	185,457			$	73.87
	Granted	78,292			69.54
	Vested	(61,787	)		64.33
	Forfeited	(3,470	)		78.5
	Unvested at March 31, 2015	198,492			$	75.05
	Performance shares are awards for which the vesting will occur based on market or performance conditions. The following table sets forth a summary of performance-based awards for the three months ended March 31, 2015:
		Awards			Weighted-
					Average
					Fair
					Value
	Unvested at December 31, 2014	130,004			$	80.21
	Granted	59,661			67.81
	Vested	(38,869	)		72.25
	Forfeited	(9,616	)		86.09
	Unvested at March 31, 2015	141,180			$	76.77
	The fair value of the performance shares granted during the three months ended March 31, 2015 was estimated using the following weighted-average assumptions:
	Weighted-Average Assumptions
	Grant date share price	$	69.54
	WESCO expected volatility	26.9		%
	Peer group median volatility	23.2		%
	Risk-free interest rate	1.05		%
	Correlation	95.8		%
	The unvested performance-based awards in the table above include 70,590 shares in which vesting of the ultimate number of shares underlying such awards is dependent upon WESCO's total stockholder return in relation to the total stockholder return of a select group of peer companies over a three-year period. These awards are valued using a Monte Carlo simulation model. The probability of meeting the market criteria was considered when calculating the estimated fair market value on the date of grant. These awards are accounted for as awards with market conditions, in which compensation cost is recognized over the service period, regardless of whether the market conditions are achieved and the awards ultimately vest.
	Vesting of the remaining 70,590 shares of performance-based awards in the table above is dependent upon the three-year average growth rate of WESCO's net income. These awards are valued based upon the grant-date closing price of WESCO's common stock. These awards are accounted for as awards with performance conditions, in which 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.
	WESCO recognized $3.8 million and $4.2 million of non-cash stock-based compensation expense, which is included in selling, general and administrative expenses, for the three months ended March 31, 2015 and 2014, respectively. As of March 31, 2015, there was $29.7 million of total unrecognized compensation cost related to non-vested stock-based compensation arrangements for all awards previously made, of which approximately $11.5 million is expected to be recognized over the remainder of 2015, $11.4 million in 2016, $6.1 million in 2017 and $0.7 million in 2018.
	During the three months ended March 31, 2015 and 2014, the total intrinsic value of all awards exercised and vested was $7.7 million and $18.4 million, respectively. The total amount of cash received from the exercise of options was $0.8 million for the three months ended March 31, 2014. The gross deferred tax benefit associated with the exercise of awards for the three months ended March 31, 2015 and 2014 totaled $2.6 million and $7.0 million, respectively, and was recorded as an increase to additional capital.

EARNINGS_PER_SHARE

EARNINGS PER SHARE	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE
	Basic earnings per share are computed by dividing net income by the weighted-average number of common shares outstanding during the period. Diluted earnings per share are computed by dividing net income by the weighted-average common shares and common share equivalents outstanding during the period. 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 dilutive equity awards and contingently convertible debt.
	The following table sets forth the details of basic and diluted earnings per share:
		Three Months Ended
		March 31,
	(In thousands of dollars, except per share data)	2015		2014
	Net income attributable to WESCO International, Inc.	$	47,031	$	51,905
	Weighted-average common shares outstanding used in computing basic earnings per share	44,406		44,348
	Common shares issuable upon exercise of dilutive equity awards	824		1,099
	Common shares issuable from contingently convertible debentures (see below for basis of calculation)	6,966		7,926
	Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share	52,196		53,373
	Earnings per share attributable to WESCO International, Inc.
	Basic	$	1.06	$	1.17
	Diluted	$	0.9	$	0.97
	For the three months ended March 31, 2015 and 2014, the computation of diluted earnings per share attributable to WESCO International, Inc. excluded approximately 0.9 million and 0.5 million stock-settled stock appreciation rights at weighted-average exercise prices of $74.94 per share and $79.13 per share, respectively. These amounts were excluded because their effect would have been antidilutive.
	Because of WESCO’s obligation to settle the par value of the 2029 Debentures in cash upon conversion, WESCO is required to include shares underlying the 2029 Debentures in its diluted weighted-average shares outstanding when the average stock price per share for the period exceeds the conversion price of the respective debentures. Only the number of shares issuable under the treasury stock method of accounting for share dilution are included, which is based upon the amount by which the average stock price exceeds the conversion price. The conversion price of the 2029 Debentures is $28.87. Share dilution is limited to a maximum of 11,948,087 shares for the 2029 Debentures. For the three months ended March 31, 2015 and 2014, the effect of the 2029 Debentures on diluted earnings per share attributable to WESCO International, Inc. was a decrease of $0.14 and $0.17, respectively.
	In December 2014, the Company's Board of Directors authorized the repurchase of up to $300 million of the Company's common stock through December 31, 2017. On February 23, 2015, the Company entered into an accelerated stock repurchase agreement (the "ASR Transaction") with a financial institution to purchase shares of its common stock. Upon inception of the ASR Transaction, on February 26, 2015, the Company paid $25 million and initially received 300,651 shares. WESCO funded the repurchase with borrowings under its revolving credit facility. The actual number of shares that the Company repurchased under the ASR Transaction was determined by the average of the volume-weighted average prices (VWAP) of the Company's common stock for each exchange business day during the settlement valuation period, which ended 60 days after the ASR Transaction was executed. The ASR Transaction settled on April 23, 2015 and the Company received an additional 63,678 shares. The additional shares received upon settlement are excluded from the computation of basic and diluted earnings per share for the three months ended March 31, 2015.

EMPLOYEE_BENEFIT_PLANS

EMPLOYEE BENEFIT PLANS	3 Months Ended
	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS
	A majority of WESCO’s employees are covered by defined contribution retirement savings plans for their services rendered subsequent to WESCO’s formation. WESCO also offers a deferred compensation plan for select individuals. For U.S. participants, WESCO will make contributions in an amount equal to 50% of the participant’s total monthly contributions up to a maximum of 6% of eligible compensation. For Canadian participants, WESCO will make contributions in an amount ranging from 3% to 5% of the participant’s eligible compensation based on years of continuous service. In addition, for U.S. participants, employer contributions may be made at the discretion of the Board of Directors. For the three months ended March 31, 2015 and 2014, WESCO incurred charges of $5.1 million and $4.8 million, respectively, for all such plans. Contributions are made in cash to defined contribution retirement savings plans. The deferred compensation plan is an unfunded plan. Employees have the option to transfer balances allocated to their accounts in the defined contribution retirement savings plan and the deferred compensation plan into any of the available investment options. An investment option for employees in the defined contribution retirement savings plan is WESCO common stock.
	In connection with the December 14, 2012 acquisition of EECOL, the Company assumed a contributory defined benefit plan covering substantially all Canadian employees of EECOL and a Supplemental Executive Retirement Plan for certain executives of EECOL. The following table reflects the components of net periodic benefit costs for the Company's defined benefit plans for the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
	(In thousands of dollars)	2015			2014
	Service cost	$	1,171		$	900
	Interest cost	1,042			1,156
	Expected return on plan assets	(1,366		)	(1,361		)
	Recognized actuarial gain	(4		)	(14		)
	Net periodic benefit cost	$	843		$	681
	During the three months ended March 31, 2015 and 2014, the Company made aggregate cash contributions of $0.5 million and $0.8 million, respectively, to its defined benefit plans.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	As initially reported in our 2008 Annual Report on Form 10-K, WESCO was a defendant in a lawsuit filed in a state court in Indiana in which a customer, ArcelorMittal Indiana Harbor, Inc. (“AIH”), alleged that the Company sold defective products to AIH in 2004 that were supplied to the Company by others. The lawsuit sought monetary damages in the amount of approximately $50 million. On February 14, 2013, the jury returned a verdict in favor of AIH and awarded damages in the amount of approximately $36.1 million, and judgment was entered on the jury's verdict. As a result, the Company recorded a $36.1 million charge to selling, general and administrative expenses in 2012. The Company received letters from its insurers confirming insurance coverage of the matter and recorded a receivable in the quarter ended March 31, 2013 in an amount equal to the previously recorded liability. The Company disputed this outcome and filed a post-trial motion challenging the verdict alleging various errors that occurred during trial. AIH also filed a post-trial motion asking the court to award additional amounts to AIH, including prejudgment and post-judgment interest. The Court denied the Company's post-trial motion on June 28, 2013 and granted in part AIH's motion, awarding prejudgment interest in the amount of $3.9 million and ordering post-judgment interest to accrue on the entire judgment at 8% per annum. In the quarter ended June 30, 2013, the Company received letters from its insurers confirming insurance coverage of all prejudgment and post-judgment interest related to the matter. The Company has recorded a liability and a corresponding receivable in the amount of $10.2 million for prejudgment and post-judgment interest. Final judgment was entered by the court on July 16, 2013, and the Company appealed the judgment. On November 10, 2014, the Indiana Court of Appeals reversed the prejudgment interest award, but otherwise affirmed the underlying judgment. A petition for further review of the case was filed with the Indiana Supreme Court.
	On April 15, 2015, the Company, AIH and the parties’ respective insurance carriers attended a mediation and agreed to settle the case. As part of the settlement, the Company's insurers paid $35.8 million to AIH on April 30, 2015 in full and final satisfaction of the judgment, including any prejudgment and post-judgment interest, and AIH agreed to release all claims against the Company and its insurers. The parties also agreed to a dismissal of the pending appeal to the Indiana Supreme Court. The settlement of this matter has no effect on the Company's financial condition or results of operations.
	WESCO is subject to the laws and regulations of states and other jurisdictions concerning the identification, reporting and escheatment (the transfer of property to the state) of unclaimed or abandoned funds, and is subject to audit and examination for compliance with these requirements. WESCO Distribution, Inc. is currently undergoing a compliance audit in the State of Delaware concerning the identification, reporting and escheatment of unclaimed or abandoned property. A third party auditor is conducting the audit on behalf of the State, and the Company has been working with an outside consultant during the audit process and in discussions with the auditors. The Company is defending the audit, the outcome of which cannot be predicted with certainty at this time. After the third party auditor completes its field work, it is expected to issue preliminary findings for review by the Company and the State, and thereafter the auditor is expected to issue a final report of examination. If the Company and State do not reach resolution after further discussion, the State issues a demand for payment, which the Company may either agree to pay or appeal, in full or in part. The Company has recorded a liability for unclaimed property based on the facts currently known to the Company.
	In October 2014, WESCO was notified that the New York County District Attorney’s Office is conducting a criminal investigation involving minority and disadvantaged business contracting practices in the construction industry in New York City and that various contractors, minority and disadvantaged business firms, and their material suppliers, including the Company, are a part of this investigation. The Company has commenced an internal review of this matter and intends to cooperate with the government investigation. The Company cannot predict the outcome or impact of the matter at this time, but could be subject to fines, penalties or other adverse consequences. Based on the facts currently known to the Company, it cannot reasonably estimate a range of exposure to potential liability at this time.

INCOME_TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES
	The effective tax rate for the three months ended March 31, 2015 and 2014 was 29.4% and 28.2%, respectively. WESCO’s effective tax rate is lower than the federal statutory rate of 35% primarily due to benefits resulting from the tax effect of intercompany financing and lower rates on foreign earnings, which are partially offset by nondeductible expenses and state taxes. The effective tax rates for the three months ended March 31, 2015 and 2014 reflect beneficial discrete adjustments totaling approximately $0.1 million in each period, primarily related to changes in state tax rates and changes in uncertain tax positions. There have been no material adjustments to liabilities relating to uncertain tax positions since the last annual disclosure for the year ended December 31, 2014.

OTHER_FINANCIAL_INFORMATION

OTHER FINANCIAL INFORMATION	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information [Abstract]
OTHER FINANCIAL INFORMATION	OTHER FINANCIAL INFORMATION
	WESCO International, Inc. ("WESCO International") has outstanding $344.9 million in aggregate principal amount of 2029 Debentures. The 2029 Debentures are fully and unconditionally guaranteed by WESCO Distribution, Inc. ("WESCO Distribution"), a 100% owned subsidiary of WESCO International, on a senior subordinated basis to all existing and future senior indebtedness of WESCO Distribution.
	WESCO Distribution has outstanding $500 million in aggregate principal amount of 5.375% Senior Notes due 2021 (the "2021 Notes"). The 2021 Notes are unsecured senior obligations of WESCO Distribution and are guaranteed on a senior unsecured basis by WESCO International.
	Condensed consolidating financial information for WESCO International, Inc., WESCO Distribution, Inc. and the non-guarantor subsidiaries is presented on the following pages.
	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	(unaudited)
		March 31, 2015
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and
		Inc.			Inc.						Eliminating
											Entries
	Cash and cash equivalents	$	—		$	39,584		$	114,767		$	—		$	154,351
	Trade accounts receivable, net	—			—			1,082,199			—			1,082,199
	Inventories, net	—			379,967			434,396			—			814,363
	Other current assets	8			142,241			126,746			(6,447		)	262,548
	Total current assets	8			561,792			1,758,108			(6,447		)	2,313,461
	Intercompany receivables, net	—			—			1,827,417			(1,827,417		)	—
	Property, buildings and equipment, net	—			56,077			117,801			—			173,878
	Intangible assets, net	—			4,568			394,105			—			398,673
	Goodwill	—			246,771			1,428,810			—			1,675,581
	Investments in affiliates	3,242,266			3,751,181			—			(6,993,447		)	—
	Other noncurrent assets	4,013			12,131			34,643			—			50,787
	Total assets	$	3,246,287		$	4,632,520		$	5,560,884		$	(8,827,311	)	$	4,612,380
	Accounts payable	$	—		$	462,609		$	309,272		$	—		$	771,881
	Short-term debt	—			—			49,663			—			49,663
	Other current liabilities	7,288			99,301			117,426			(6,447		)	217,568
	Total current liabilities	7,288			561,910			476,361			(6,447		)	1,039,112
	Intercompany payables, net	1,200,491			626,926			—			(1,827,417		)	—
	Long-term debt, net	178,576			686,200			472,105			—			1,336,881
	Other noncurrent liabilities	21,889			240,948			136,232			—			399,069
	Total WESCO International stockholders' equity	1,838,043			2,516,536			4,476,911			(6,993,447		)	1,838,043
	Noncontrolling interest	—			—			(725		)	—			(725		)
	Total liabilities and stockholders’ equity	$	3,246,287		$	4,632,520		$	5,560,884		$	(8,827,311	)	$	4,612,380
	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	(unaudited)
		December 31, 2014
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and
		Inc.			Inc.						Eliminating
											Entries
	Cash and cash equivalents	$	—		$	32,508		$	95,811		$	—		$	128,319
	Trade accounts receivable, net	—			—			1,117,420			—			1,117,420
	Inventories, net	—			373,938			445,564			—			819,502
	Other current assets	12			144,282			147,268			(6,465		)	285,097
	Total current assets	12			550,728			1,806,063			(6,465		)	2,350,338
	Intercompany receivables, net	—			—			1,806,215			(1,806,215		)	—
	Property, buildings and equipment, net	—			56,735			125,990			—			182,725
	Intangible assets, net	—			4,733			425,107			—			429,840
	Goodwill	—			246,771			1,488,669			—			1,735,440
	Investments in affiliates	3,304,914			3,828,727			—			(7,133,641		)	—
	Other noncurrent assets	4,083			12,844			39,167			—			56,094
	Total assets	$	3,309,009		$	4,700,538		$	5,691,211		$	(8,946,321	)	$	4,754,437
	Accounts payable	$	—		$	445,680		$	319,455		$	—		$	765,135
	Short-term debt	—			—			46,787			—			46,787
	Other current liabilities	12,465			113,746			132,204			(6,465		)	251,950
	Total current liabilities	12,465			559,426			498,446			(6,465		)	1,063,872
	Intercompany payables, net	1,168,366			637,849			—			(1,806,215		)	—
	Long-term debt, net	177,638			683,407			505,385			—			1,366,430
	Other noncurrent liabilities	21,888			232,544			141,538			—			395,970
	Total WESCO International stockholders' equity	1,928,652			2,587,312			4,546,329			(7,133,641		)	1,928,652
Noncontrolling interest	—			—			(487		)	—			(487		)
Total liabilities and stockholders’ equity	$	3,309,009		$	4,700,538		$	5,691,211		$	(8,946,321	)	$	4,754,437
WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
(unaudited)
	Three Months Ended
	March 31, 2015
	(In thousands of dollars)
	WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
	International,			Distribution,			Subsidiaries			and
	Inc.			Inc.						Eliminating
										Entries
Net sales	$	—		$	839,282		$	1,005,250		$	(28,202	)	$	1,816,330
Cost of goods sold (excluding depreciation and
amortization)	—			669,806			807,035			(28,202		)	1,448,639
Selling, general and administrative expenses	8			136,411			128,166			—			264,585
Depreciation and amortization	—			4,834			11,087			—			15,921
Results of affiliates’ operations	51,165			36,268			—			(87,433		)	—
Interest expense, net	6,187			18,640			(3,933		)	—			20,894
Provision for income taxes	(1,822		)	2,821			18,499			—			19,498
Net income	46,792			43,038			44,396			(87,433		)	46,793
Net loss attributable to noncontrolling interest	—			—			(238		)	—			(238		)
Net income attributable to WESCO International, Inc.	$	46,792		$	43,038		$	44,634		$	(87,433	)	$	47,031
Other comprehensive loss:
Foreign currency translation adjustments	(113,814		)	(113,814		)	(113,814		)	227,628			(113,814		)
Comprehensive loss attributable to WESCO International, Inc.	$	(67,022	)	$	(70,776	)	$	(69,180	)	$	140,195		$	(66,783	)
	Three Months Ended
	31-Mar-14
	(In thousands of dollars)
	WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
	International,			Distribution,			Subsidiaries			and
	Inc.			Inc.						Eliminating
										Entries
Net sales	$	—		$	829,471		$	1,007,453		$	(26,099	)	$	1,810,825
Cost of goods sold (excluding depreciation and
amortization)	—			658,584			803,547			(26,099		)	1,436,032
Selling, general and administrative expenses	—			136,680			128,782			—			265,462
Depreciation and amortization	—			4,700			11,672			—			16,372
Results of affiliates’ operations	56,210			40,713			—			(96,923		)	—
Interest expense, net	6,070			18,761			(4,143		)	—			20,688
Provision for income taxes	(1,715		)	3,047			19,084			—			20,416
Net income	51,855			48,412			48,511			(96,923		)	51,855
Net loss attributable to noncontrolling interest	—			—			(50		)	—			(50		)
Net income attributable to WESCO International, Inc.	$	51,855		$	48,412		$	48,561		$	(96,923	)	$	51,905
Other comprehensive income:
Foreign currency translation adjustments	(46,500		)	(46,500		)	(46,500		)	93,000			(46,500		)
Comprehensive income attributable to WESCO International, Inc.	$	5,355		$	1,912		$	2,061		$	(3,923	)	$	5,405
WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
(unaudited)
	Three Months Ended
	31-Mar-15
	(In thousands of dollars)
	WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
	International,			Distribution,			Subsidiaries			and Eliminating
	Inc.			Inc.						Entries
Net cash provided by (used in) operating activities	$	(4,441	)	$	53,333		$	41,164		$	—		$	90,056
Investing activities:
Capital expenditures	—			(4,005		)	(1,021		)	—			(5,026		)
Other	—			(32,125		)	785			32,125			785
Net cash used in investing activities	—			(36,130		)	(236		)	32,125			(4,241		)
Financing activities:
Borrowings	32,125			218,699			150,600			(32,125		)	369,299
Repayments	—			(221,699		)	(166,580		)	—			(388,279		)
Equity activities	(27,602		)	—			—			—			(27,602		)
Other	(82		)	(7,127		)	—			—			(7,209		)
Net cash provided by (used in) financing activities	4,441			(10,127		)	(15,980		)	(32,125		)	(53,791		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(5,992		)	—			(5,992		)
Net change in cash and cash equivalents	—			7,076			18,956			—			26,032
Cash and cash equivalents at the beginning of period	—			32,508			95,811			—			128,319
Cash and cash equivalents at the end of period	$	—		$	39,584		$	114,767		$	—		$	154,351
WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
(unaudited)
	Three Months Ended
	31-Mar-14
	(In thousands of dollars)
	WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
	International,			Distribution,			Subsidiaries			and Eliminating
	Inc.			Inc.						Entries
Net cash (used in) provided by operating activities	$	(4,871	)	$	20,415		$	31,169		$	—		$	46,713
Investing activities:
Capital expenditures	—			(3,347		)	(1,665		)	—			(5,012		)
Acquisition payments	—			—			(91,187		)	—			(91,187		)
Other	—			(5,169		)	39			5,169			39
Net cash used in investing activities	—			(8,516		)	(92,813		)	5,169			(96,160		)
Financing activities:
Borrowings	5,168			307,851			115,575			(5,169		)	423,425
Repayments	—			(307,851		)	(95,592		)	—			(403,443		)
Equity activities	(5,331		)	—			—			—			(5,331		)
Other	5,034			3,858			(4		)	—			8,888
Net cash provided by financing activities	4,871			3,858			19,979			(5,169		)	23,539
Effect of exchange rate changes on cash and cash equivalents	—			—			(1,461		)	—			(1,461		)
Net change in cash and cash equivalents	—			15,757			(43,126		)	—			(27,369		)
Cash and cash equivalents at the beginning of period	—			31,695			92,030			—			123,725
Cash and cash equivalents at the end of period	$	—		$	47,452		$	48,904		$	—		$	96,356
The unaudited Condensed Consolidated Statements of Cash Flows include certain reclassifications to previously reported amounts to conform to the current period presentation.

Subsequent_Events_SUBSEQUENT_E

Subsequent Events SUBSEQUENT EVENTS (Notes)	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events [Text Block]	SUBSEQUENT EVENTS
	The Company evaluated subsequent events and concluded that no subsequent events have occurred that would require recognition in the unaudited Condensed Consolidated Financial Statements or disclosure in the Notes thereto expect as described below.
	On May 1, 2015, WESCO International, Inc., through its wholly-owned subsidiary WESCO Distribution, Inc., completed its acquisition of Hill Country Electric Supply, LP, an electrical distributor headquartered in Austin, Texas focused on the commercial construction market with annual sales of approximately $140 million from nine locations in Central and South Texas. WESCO funded the purchase price paid at closing with cash, and borrowings under the Receivables Facility and the Revolving Credit Facility. A preliminary purchase price allocation will be completed during the second quarter of 2015

ACCOUNTING_POLICIES_Policies

ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2015
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’s 2014 Annual Report on Form 10-K as filed with the SEC on February 24, 2015. The Condensed Consolidated Balance Sheet at December 31, 2014 was derived from the audited Consolidated Financial Statements as of that date, but does not include all of the disclosures required by accounting principles generally accepted in the United States of America.
	The unaudited Condensed Consolidated Balance Sheet as of March 31, 2015, the unaudited Condensed Consolidated Statements of Comprehensive Income (Loss) for the three months ended March 31, 2015 and 2014, respectively, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2015 and 2014, 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.
Reclassification	The Condensed Consolidated Balance Sheet at December 31, 2014 and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2014 include certain reclassifications to previously reported amounts to conform to the current period presentation.
Fair Value of Financial Instruments	Fair Value of Financial Instruments
	The Company measures the fair value of financial assets and liabilities in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 820, "Fair Value Measurements and Disclosures," which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements.
	ASC 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows:
	•	Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date.
	•	Level 2 inputs include inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities.
	•	Level 3 inputs are unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.
	At March 31, 2015, the carrying value of WESCO’s 6.0% Convertible Senior Debentures due 2029 (the "2029 Debentures") was $178.6 million and the fair value was approximately $849.8 million. At December 31, 2014, the carrying value of WESCO’s 2029 Debentures was $177.6 million and the fair value was approximately $936.1 million. The reported carrying amounts of WESCO’s other debt instruments approximate their fair values. The Company uses a market approach to fair value all of its debt instruments, utilizing quoted prices in active markets, interest rates and other relevant information generated by market transactions involving similar instruments. Therefore, all of the Company's debt instruments are classified as Level 2 within the valuation hierarchy. For all of the Company's remaining financial instruments, consisting of cash and cash equivalents, accounts receivable, accounts payable and other accrued liabilities, carrying values are considered to approximate fair value due to the short maturity of these instruments.
New Accounting Pronouncements, Policy [Policy Text Block]	New Accounting Pronouncements
	In May 2014, the FASB and International Accounting Standards Board issued a converged final standard on the recognition of revenue from contracts with customers. This updated guidance provides a framework for addressing revenue recognition issues and replaces almost all existing revenue recognition guidance in current U.S. generally accepted accounting principles. The core principle of the new standard is for companies to recognize revenue to depict the transfer of goods or services to customers in amounts that reflect the consideration to which the company expects to be entitled in exchange for those goods or services. The new standard will also result in enhanced disclosures about revenue, provide guidance for transactions that were not previously addressed comprehensively, and improve guidance for multiple-element arrangements. This guidance is effective for interim and annual periods beginning after December 15, 2016. Management is currently evaluating the future impact of this guidance on WESCO's financial position, results of operations and cash flows.
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The amendments in this Update require a reporting entity to treat a performance target that affects vesting and could be achieved after the requisite service period as a performance condition. A reporting entity should apply FASB ASC Topic 718, Compensation—Stock Compensation, to awards with performance conditions that affect vesting. For all entities, ASU 2014-12 is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. This ASU may be adopted either prospectively for share-based payment awards granted or modified on or after the effective date, or retrospectively, using a modified retrospective approach. The modified retrospective approach would apply to share-based payment awards outstanding as of the beginning of the earliest annual period presented in the financial statements on adoption and to all new or modified awards thereafter. The adoption of this guidance is not expected to have an impact on WESCO's consolidated financial statements and notes thereto.
	In September 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. This ASU describes how an entity should assess its ability to meet obligations and sets disclosure requirements for how this information should be disclosed in the financial statements. The standard provides accounting guidance that will be used with existing auditing standards. The amendments in this ASU are effective for the annual period ending after December 15, 2016 and for annual periods and interim periods thereafter. Early application is permitted. The adoption of this guidance is not expected to have an impact on WESCO's consolidated financial statements and notes thereto.
	In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs. To simplify the presentation of debt issuance costs, the amendments in this Update require that debt issuance costs related to a recognized liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this Update. For public business entities, this ASU is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within fiscal years beginning after December 15, 2016. Early adoption is permitted for financial statements that have not been previously issued. An entity should apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. Upon transition, an entity is required to comply with the applicable disclosures for a change in an accounting principle. These disclosures include the nature of and reason for the change in accounting principle, the transition method, a description of the prior-period information that has been retrospectively adjusted, and the effect of the change on the financial statement line items (that is, debt issuance cost asset and the debt liability). Management is currently evaluating the future impact of this guidance on WESCO's financial position, results of operations and cash flows.

ACQUISITIONS_Tables

ACQUISITIONS (Tables)	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]
	(In thousands of dollars)
	Fair value of assets acquired	$	104,601
	Fair value of liabilities assumed	13,414
	Cash paid for acquisitions	$	91,187

STOCKBASED_COMPENSATION_Tables

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	During the three months ended March 31, 2015 and 2014, WESCO granted the following stock-settled appreciation rights, restricted stock units and performance-based awards at the following weighted-average fair values and assumptions:
		Three Months Ended
		March 31,			March 31,
		2015			2014
	Stock-settled appreciation rights granted	394,182			272,213
	Weighted-average fair value	$	21.68		$	30.66
	Restricted stock units granted	78,292			62,506
	Weighted-average fair value	$	69.54		$	85.35
	Performance-based awards granted	59,661			44,046
	Weighted-average fair value	$	67.81		$	86.65
Schedule of Share-based Compensation, Stock Options and Stock Appreciation Rights Award Activity [Table Text Block]	The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2015:
		Awards		Weighted-			Weighted-	Aggregate
				Average			Average	Intrinsic
				Exercise			Remaining	Value
				Price			Contractual Term (In years)	(In thousands)
	Outstanding at December 31, 2014	2,480,745		$	50.91
	Granted	394,182		69.54
	Exercised	(27,316	)	40.78
	Forfeited	(7,800	)	81.12
	Outstanding at March 31, 2015	2,839,811		53.51			5.6	$	51,128.90
	Exercisable at March 31, 2015	2,190,049		$	47.4		4.5	$	50,956.50
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	The following table sets forth a summary of time-based restricted stock units and related information for the three months ended March 31, 2015:
		Awards		Weighted-
				Average
				Fair
				Value
	Unvested at December 31, 2014	185,457		$	73.87
	Granted	78,292		69.54
	Vested	(61,787	)	64.33
	Forfeited	(3,470	)	78.5
	Unvested at March 31, 2015	198,492		$	75.05
Schedule of Nonvested Performance-based Units Activity [Table Text Block]	The following table sets forth a summary of performance-based awards for the three months ended March 31, 2015:
		Awards		Weighted-
				Average
				Fair
				Value
	Unvested at December 31, 2014	130,004		$	80.21
	Granted	59,661		67.81
	Vested	(38,869	)	72.25
	Forfeited	(9,616	)	86.09
	Unvested at March 31, 2015	141,180		$	76.77

EARNINGS_PER_SHARE_Tables

EARNINGS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table sets forth the details of basic and diluted earnings per share:
		Three Months Ended
		March 31,
	(In thousands of dollars, except per share data)	2015		2014
	Net income attributable to WESCO International, Inc.	$	47,031	$	51,905
	Weighted-average common shares outstanding used in computing basic earnings per share	44,406		44,348
	Common shares issuable upon exercise of dilutive equity awards	824		1,099
	Common shares issuable from contingently convertible debentures (see below for basis of calculation)	6,966		7,926
	Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share	52,196		53,373
	Earnings per share attributable to WESCO International, Inc.
	Basic	$	1.06	$	1.17
	Diluted	$	0.9	$	0.97

EMPLOYEE_BENEFIT_PLANS_Schedul

EMPLOYEE BENEFIT PLANS Schedule of Net Benefit Costs (Tables)	3 Months Ended
	Mar. 31, 2015
Postemployment Benefits [Abstract]
Schedule of Net Benefit Costs [Table Text Block]	The following table reflects the components of net periodic benefit costs for the Company's defined benefit plans for the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
	(In thousands of dollars)	2015			2014
	Service cost	$	1,171		$	900
	Interest cost	1,042			1,156
	Expected return on plan assets	(1,366		)	(1,361		)
	Recognized actuarial gain	(4		)	(14		)
	Net periodic benefit cost	$	843		$	681

OTHER_FINANCIAL_INFORMATION_Ta

OTHER FINANCIAL INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2015
Condensed Balance Sheet Statements, Captions [Line Items]
Condensed Balance Sheet [Table Text Block]	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	(unaudited)
		March 31, 2015
		(In thousands of dollars)
		WESCO		WESCO		Non-Guarantor			Consolidating			Consolidated
		International,		Distribution,		Subsidiaries			and
		Inc.		Inc.					Eliminating
									Entries
	Cash and cash equivalents	$	—	$	39,584	$	114,767		$	—		$	154,351
	Trade accounts receivable, net	—		—		1,082,199			—			1,082,199
	Inventories, net	—		379,967		434,396			—			814,363
	Other current assets	8		142,241		126,746			(6,447		)	262,548
	Total current assets	8		561,792		1,758,108			(6,447		)	2,313,461
	Intercompany receivables, net	—		—		1,827,417			(1,827,417		)	—
	Property, buildings and equipment, net	—		56,077		117,801			—			173,878
	Intangible assets, net	—		4,568		394,105			—			398,673
	Goodwill	—		246,771		1,428,810			—			1,675,581
	Investments in affiliates	3,242,266		3,751,181		—			(6,993,447		)	—
	Other noncurrent assets	4,013		12,131		34,643			—			50,787
	Total assets	$	3,246,287	$	4,632,520	$	5,560,884		$	(8,827,311	)	$	4,612,380
	Accounts payable	$	—	$	462,609	$	309,272		$	—		$	771,881
	Short-term debt	—		—		49,663			—			49,663
	Other current liabilities	7,288		99,301		117,426			(6,447		)	217,568
	Total current liabilities	7,288		561,910		476,361			(6,447		)	1,039,112
	Intercompany payables, net	1,200,491		626,926		—			(1,827,417		)	—
	Long-term debt, net	178,576		686,200		472,105			—			1,336,881
	Other noncurrent liabilities	21,889		240,948		136,232			—			399,069
	Total WESCO International stockholders' equity	1,838,043		2,516,536		4,476,911			(6,993,447		)	1,838,043
	Noncontrolling interest	—		—		(725		)	—			(725		)
	Total liabilities and stockholders’ equity	$	3,246,287	$	4,632,520	$	5,560,884		$	(8,827,311	)	$	4,612,380
	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	(unaudited)
		December 31, 2014
		(In thousands of dollars)
		WESCO		WESCO		Non-Guarantor			Consolidating			Consolidated
		International,		Distribution,		Subsidiaries			and
		Inc.		Inc.					Eliminating
									Entries
	Cash and cash equivalents	$	—	$	32,508	$	95,811		$	—		$	128,319
	Trade accounts receivable, net	—		—		1,117,420			—			1,117,420
	Inventories, net	—		373,938		445,564			—			819,502
	Other current assets	12		144,282		147,268			(6,465		)	285,097
	Total current assets	12		550,728		1,806,063			(6,465		)	2,350,338
	Intercompany receivables, net	—		—		1,806,215			(1,806,215		)	—
	Property, buildings and equipment, net	—		56,735		125,990			—			182,725
	Intangible assets, net	—		4,733		425,107			—			429,840
	Goodwill	—		246,771		1,488,669			—			1,735,440
	Investments in affiliates	3,304,914		3,828,727		—			(7,133,641		)	—
	Other noncurrent assets	4,083		12,844		39,167			—			56,094
	Total assets	$	3,309,009	$	4,700,538	$	5,691,211		$	(8,946,321	)	$	4,754,437
	Accounts payable	$	—	$	445,680	$	319,455		$	—		$	765,135
	Short-term debt	—		—		46,787			—			46,787
	Other current liabilities	12,465		113,746		132,204			(6,465		)	251,950
	Total current liabilities	12,465		559,426		498,446			(6,465		)	1,063,872
	Intercompany payables, net	1,168,366		637,849		—			(1,806,215		)	—
	Long-term debt, net	177,638		683,407		505,385			—			1,366,430
	Other noncurrent liabilities	21,888		232,544		141,538			—			395,970
	Total WESCO International stockholders' equity	1,928,652		2,587,312		4,546,329			(7,133,641		)	1,928,652
	Noncontrolling interest	—		—		(487		)	—			(487		)
	Total liabilities and stockholders’ equity	$	3,309,009	$	4,700,538	$	5,691,211		$	(8,946,321	)	$	4,754,437

OTHER_FINANCIAL_INFORMATION_Co

OTHER FINANCIAL INFORMATION Condensed Income Statement (Tables)	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Income Statement [Table Text Block]
		Three Months Ended
		31-Mar-14
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and
		Inc.			Inc.						Eliminating
											Entries
	Net sales	$	—		$	829,471		$	1,007,453		$	(26,099	)	$	1,810,825
	Cost of goods sold (excluding depreciation and
	amortization)	—			658,584			803,547			(26,099		)	1,436,032
	Selling, general and administrative expenses	—			136,680			128,782			—			265,462
	Depreciation and amortization	—			4,700			11,672			—			16,372
	Results of affiliates’ operations	56,210			40,713			—			(96,923		)	—
	Interest expense, net	6,070			18,761			(4,143		)	—			20,688
	Provision for income taxes	(1,715		)	3,047			19,084			—			20,416
	Net income	51,855			48,412			48,511			(96,923		)	51,855
	Net loss attributable to noncontrolling interest	—			—			(50		)	—			(50		)
	Net income attributable to WESCO International, Inc.	$	51,855		$	48,412		$	48,561		$	(96,923	)	$	51,905
	Other comprehensive income:
	Foreign currency translation adjustments	(46,500		)	(46,500		)	(46,500		)	93,000			(46,500		)
	Comprehensive income attributable to WESCO International, Inc.	$	5,355		$	1,912		$	2,061		$	(3,923	)	$	5,405
	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
	(unaudited)
		Three Months Ended
		March 31, 2015
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and
		Inc.			Inc.						Eliminating
											Entries
	Net sales	$	—		$	839,282		$	1,005,250		$	(28,202	)	$	1,816,330
	Cost of goods sold (excluding depreciation and
	amortization)	—			669,806			807,035			(28,202		)	1,448,639
	Selling, general and administrative expenses	8			136,411			128,166			—			264,585
	Depreciation and amortization	—			4,834			11,087			—			15,921
	Results of affiliates’ operations	51,165			36,268			—			(87,433		)	—
	Interest expense, net	6,187			18,640			(3,933		)	—			20,894
	Provision for income taxes	(1,822		)	2,821			18,499			—			19,498
	Net income	46,792			43,038			44,396			(87,433		)	46,793
	Net loss attributable to noncontrolling interest	—			—			(238		)	—			(238		)
	Net income attributable to WESCO International, Inc.	$	46,792		$	43,038		$	44,634		$	(87,433	)	$	47,031
	Other comprehensive loss:
	Foreign currency translation adjustments	(113,814		)	(113,814		)	(113,814		)	227,628			(113,814		)
	Comprehensive loss attributable to WESCO International, Inc.	$	(67,022	)	$	(70,776	)	$	(69,180	)	$	140,195		$	(66,783	)

OTHER_FINANCIAL_INFORMATION_Co1

OTHER FINANCIAL INFORMATION Condensed Cash Flow Statement (Tables)	3 Months Ended
	Mar. 31, 2015
Condensed Cash Flow Statements, Captions [Line Items]
Condensed Cash Flow Statement [Table Text Block]	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
	(unaudited)
		Three Months Ended
		31-Mar-14
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and Eliminating
		Inc.			Inc.						Entries
	Net cash (used in) provided by operating activities	$	(4,871	)	$	20,415		$	31,169		$	—		$	46,713
	Investing activities:
	Capital expenditures	—			(3,347		)	(1,665		)	—			(5,012		)
	Acquisition payments	—			—			(91,187		)	—			(91,187		)
	Other	—			(5,169		)	39			5,169			39
	Net cash used in investing activities	—			(8,516		)	(92,813		)	5,169			(96,160		)
	Financing activities:
	Borrowings	5,168			307,851			115,575			(5,169		)	423,425
	Repayments	—			(307,851		)	(95,592		)	—			(403,443		)
	Equity activities	(5,331		)	—			—			—			(5,331		)
	Other	5,034			3,858			(4		)	—			8,888
	Net cash provided by financing activities	4,871			3,858			19,979			(5,169		)	23,539
	Effect of exchange rate changes on cash and cash equivalents	—			—			(1,461		)	—			(1,461		)
	Net change in cash and cash equivalents	—			15,757			(43,126		)	—			(27,369		)
	Cash and cash equivalents at the beginning of period	—			31,695			92,030			—			123,725
	Cash and cash equivalents at the end of period	$	—		$	47,452		$	48,904		$	—		$	96,356
	WESCO INTERNATIONAL, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
	(unaudited)
		Three Months Ended
		31-Mar-15
		(In thousands of dollars)
		WESCO			WESCO			Non-Guarantor			Consolidating			Consolidated
		International,			Distribution,			Subsidiaries			and Eliminating
		Inc.			Inc.						Entries
	Net cash provided by (used in) operating activities	$	(4,441	)	$	53,333		$	41,164		$	—		$	90,056
	Investing activities:
	Capital expenditures	—			(4,005		)	(1,021		)	—			(5,026		)
	Other	—			(32,125		)	785			32,125			785
	Net cash used in investing activities	—			(36,130		)	(236		)	32,125			(4,241		)
	Financing activities:
	Borrowings	32,125			218,699			150,600			(32,125		)	369,299
	Repayments	—			(221,699		)	(166,580		)	—			(388,279		)
	Equity activities	(27,602		)	—			—			—			(27,602		)
	Other	(82		)	(7,127		)	—			—			(7,209		)
	Net cash provided by (used in) financing activities	4,441			(10,127		)	(15,980		)	(32,125		)	(53,791		)
	Effect of exchange rate changes on cash and cash equivalents	—			—			(5,992		)	—			(5,992		)
	Net change in cash and cash equivalents	—			7,076			18,956			—			26,032
	Cash and cash equivalents at the beginning of period	—			32,508			95,811			—			128,319
	Cash and cash equivalents at the end of period	$	—		$	39,584		$	114,767		$	—		$	154,351

ORGANIZATION_Details

ORGANIZATION (Details)	Mar. 31, 2015
	distribution_centers
	countries
	customers
Restructuring Cost and Reserve [Line Items]
Active customers (in customers)	75,000
Full service branches (in branches)	9
Additional countries (in countries)	16
Hazmasters, Inc. [Member]
Restructuring Cost and Reserve [Line Items]
Full service branches (in branches)	14

ACCOUNTING_POLICIES_Details

ACCOUNTING POLICIES (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Accounting Policies [Abstract]
Long-term Debt, Fair Value	$849.80	$936.10
Fixed Rate Debt, Par Value	$178.60	$177.60

ACQUISITIONS_ACQUISITIONS_Deta

ACQUISITIONS - ACQUISITIONS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		$104,601,000
Payments to Acquire Businesses, Gross		91,187,000
Finite-Lived Customer Relationships, Gross	38,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		13,414,000
Other Indefinite-lived Intangible Assets	300,000
LaPrairie, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period	30,000,000
Goodwill, Acquired During Period		8,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	11,000,000
Hazmasters, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period	80,000,000
Goodwill, Acquired During Period		29,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	28,100,000
Number of Stores	14
Hi-Line [Member]
Business Acquisition [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period	30,000,000
Goodwill, Acquired During Period		24,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	14,200,000
Supplier Relationships [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	3,200,000
Trademarks [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$10,900,000
Minimum [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	2 years
Minimum [Member] | Trademarks [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Maximum [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years
Maximum [Member] | Trademarks [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years

SCHEDULE_OF_SHAREBASED_COMPENS

SCHEDULE OF SHARE-BASED COMPENSATION, STOCK OPTIONS AND STOCK APPRECIATION RIGHTS AWARD ACTIVITY (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$69.54
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$53.51		$50.91
Share-based Compensation Arrangement By Share-based Payment Award, Options and Stock Appreciation Rights, Outstanding [Roll Forward]
Grants in Period (in shares)	394,182
Exercises in Period (in shares)	27,316
Forfeitures in Period (in shares)	7,800
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	$40.78
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	$81.12
Weighted Average Exercise Price, Exercisable (in dollars per share)	$47.40
Weighted Average Remaining Contractual Term, Outstanding (in years)	5 years 7 months 17 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested	$51,128,900
Weighted Average Remaining Contractual Term, Exercisable (in years)	4 years 6 months
Aggregate Intrinsic Value, Outstanding	$50,956,500
Performance-based awards outstanding (in shares)	70,590		2,480,745
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, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$21.68	$30.66
Share-based Compensation Arrangement By Share-based Payment Award, Options and Stock Appreciation Rights, Outstanding [Roll Forward]
Grants in Period (in shares)	394,182	272,213
Performance-based awards outstanding (in shares)	2,839,811

SCHEDULE_OF_SHAREBASED_PAYMENT

SCHEDULE OF SHARE-BASED PAYMENT AWARD, VALUATION ASSUMPTIONS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	394,182
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$69.54
Risk free interest rate	1.60%	1.50%
Expected life (in years)	5 years	5 years
WESCO expected volatility	32.00%	39.00%
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	394,182	272,213
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$21.68	30.66
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	78,292	62,506
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$69.54	85.35
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	59,661	44,046
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$67.81	86.65
Risk free interest rate	0.00%
WESCO expected volatility	0.00%

SUMMARY_OF_RESTRICTED_STOCK_UN

SUMMARY OF RESTRICTED STOCK UNITS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	70,590		2,480,745
Granted (in shares)	394,182
Unvested, Weighted Average Fair Value (in dollars per share)	$53.51		$50.91
Granted, Weighted Average Fair Value (in dollars per share)	$69.54
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$81.12
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	198,492		185,457
Granted (in shares)	78,292	62,506
Vested (in shares)	-61,787
Forfeited (in shares)	-3,470
Unvested, Weighted Average Fair Value (in dollars per share)	$75.05		$73.87
Granted, Weighted Average Fair Value (in dollars per share)	$69.54	$85.35
Vested in Period, Weighted Average Fair Value (in dollars per share)	$64.33
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$78.50

SUMMARY_OF_PERFORMANCEBASED_AW

SUMMARY OF PERFORMANCE-BASED AWARDS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	70,590		2,480,745
Granted (in shares)	394,182
Unvested, Weighted Average Fair Value (in dollars per share)	$53.51		$50.91
Granted, Weighted Average Fair Value (in dollars per share)	$69.54
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$81.12
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	141,180		130,004
Granted (in shares)	59,661	44,046
Vested (in shares)	-38,869
Forfeited (in shares)	-9,616
Unvested, Weighted Average Fair Value (in dollars per share)	$76.77		$80.21
Granted, Weighted Average Fair Value (in dollars per share)	$67.81	$86.65
Vested in Period, Weighted Average Fair Value (in dollars per share)	$72.25
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$86.09

SCHEDULE_OF_SHAREBASED_PAYMENT1

SCHEDULE OF SHARE-BASED PAYMENT AWARD, PERFORMANCE-BASED AWARDS, VALUATION ASSUMPTIONS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price	$69.54
WESCO expected volatility	32.00%	39.00%
Risk free interest rate	1.60%	1.50%
Correlation	100.00%
Fair Value Assumptions, Expected Volatility Rate	0.00%
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
WESCO expected volatility	0.00%
Risk free interest rate	0.00%

STOCKBASED_COMPENSATION_Detail

STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended		9 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Weighted Average Fair Value (in dollars per share)	$69.54
Performance-based awards outstanding (in shares)	70,590						2,480,745
Stock-based compensation expense	$3.80	$4.20	$11.50	$0.70	$6.10	$11.40
Total unrecognized compensation cost	29.7
Total intrinsic value of awards exercised	7.7	18.4
Cash received from exercise of options		0.8
Tax benefit associated with exercise of awards	$2.60	$7
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Weighted Average Fair Value (in dollars per share)	$21.68	$30.66
Performance-based awards outstanding (in shares)	2,839,811
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Weighted Average Fair Value (in dollars per share)	$69.54	$85.35
Performance-based awards outstanding (in shares)	198,492						185,457
Performance-based Awards - Peer Group Total Shareholder Return [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Weighted Average Fair Value (in dollars per share)	$67.81	$86.65
Performance-based awards outstanding (in shares)	141,180						130,004

SCHEDULE_OF_EARNINGS_PER_SHARE

SCHEDULE OF EARNINGS PER SHARE, BASIC AND DILUTED (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Net income (loss) attributable to WESCO International, Inc.	$47,031	$51,905
Weighted average common shares outstanding used in computing basic earnings per share (in shares)	44,406	44,348
Common shares issuable upon exercise of dilutive stock options (in shares)	824	1,099
Common shares issuable from contingently convertible debentures (in shares)	6,966	7,926
Weighted average common shares outstanding and common share equivalents used in computing diluted earnings per share (in shares)	52,196	53,373
Earnings Per Share, Basic and Diluted [Abstract]
Basic (in dollars per share)	$1.06	$1.17
Diluted (in dollars per share)	$0.90	$0.97

EARNINGS_PER_SHARE_Details

EARNINGS PER SHARE (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Earnings Per Share Dilution Limit (in shares)	6,966,000	7,926,000
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Earnings Per Share Dilution Limit (in shares)	11,948,087
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	900,000	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	74.94	79.13
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Debt Instrument, Convertible, Conversion Price (in dollars per share)	28.87
Dilutive Securities, Effect on Basic Earnings Per Share	0.14	0.17

EARNINGS_PER_SHARE_Accelerated

EARNINGS PER SHARE Accelerated Share Repurchase (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Accelerated Share Repurchases [Line Items]
Payments for Repurchase of Common Stock	$27,602,000	$5,331,000
Stock Repurchase Program, Authorized Amount	300,000,000
Treasury Stock, Shares, Acquired	300,651
Accelerated Share Repurchases, Adjustment to Recorded Amount	63,678
Repurchase Agreements [Member]
Accelerated Share Repurchases [Line Items]
Payments for Repurchase of Common Stock	$25,000,000

EMPLOYEE_BENEFIT_PLANS_Details

EMPLOYEE BENEFIT PLANS (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Defined Benefit Plan, Contributions by Employer	$500,000	$800,000
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan, Cost Recognized	$5,100,000	$4,800,000
UNITED STATES
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Employer Matching Contribution Percent	50.00%
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	6.00%
Minimum [Member] | CANADA
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	3.00%
Maximum [Member] | CANADA
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	5.00%

EMPLOYEE_BENEFIT_PLANS_EMPLOYE

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS Pension Costs (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Defined Benefit Plan, Contributions by Employer	$500,000	$800,000
Service cost	1,171,000	900,000
Interest cost	1,042,000	1,156,000
Expected return on plan assets	-1,366,000	-1,361,000
Defined Benefit Plan, Actuarial Gain (Loss)	-4,000	-14,000
Net periodic benefit cost	$843,000	$681,000

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Loss Contingencies [Line Items]
Loss Contingency, Receivable, Receipts	$35.80
Loss Contingency, Accrual, Current	3.9
Loss Contingency, Receivable, Current	10.2
Damages sought	50
Damages awarded	$36.10

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Tax Contingency [Line Items]
Effective tax rate	29.40%	28.20%
Federal statutory rate	35.00%
Effective Income Tax Rate Reconciliation, Tax Contingency, Other, Percent	$100,000

OTHER_FINANCIAL_INFORMATION_De

OTHER FINANCIAL INFORMATION (Details) (USD $)	Mar. 31, 2015
In Millions, unless otherwise specified
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	5.38%
Convertible Senior Debentures Due in 2029 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	344.9
Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	500

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Condensed Financial Information [Line Items]
Cash and cash equivalents	$154,351	$128,319	$96,356	$123,725
Trade accounts receivable, net	1,082,199	1,117,420
Inventories, net	814,363	819,502
Other current assets	262,548	285,097
Total current assets	2,313,461	2,350,338
Intercompany receivables, net	0	0
Property, buildings and equipment, net	173,878	182,725
Intangible assets, net	398,673	429,840
Goodwill and other intangibles, net	1,675,581	1,735,440
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Other assets	50,787	56,094
Total assets	4,612,380	4,754,437
Accounts payable	771,881	765,135
Short-term debt	49,663	46,787
Other Liabilities, Current	217,568	251,950
Total current liabilities	1,039,112	1,063,872
Intercompany payables, net	0	0
Long-term debt	1,336,881	1,366,430
Liabilities, Other than Long-term Debt, Noncurrent	399,069	395,970
Total stockholders' equity	1,838,043	1,928,652
Stockholders' Equity Attributable to Noncontrolling Interest	725	487
Total liabilities and stockholders' equity	4,612,380	4,754,437
Parent Company [Member]
Condensed Financial Information [Line Items]
Cash and cash equivalents	0	0	0	0
Trade accounts receivable, net	0	0
Inventories, net	0	0
Other current assets	8	12
Total current assets	8	12
Intercompany receivables, net	0	0
Property, buildings and equipment, net	0	0
Intangible assets, net	0	0
Goodwill and other intangibles, net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	3,242,266	3,304,914
Other assets	4,013	4,083
Total assets	3,246,287	3,309,009
Accounts payable	0	0
Short-term debt	0	0
Other Liabilities, Current	7,288	12,465
Total current liabilities	7,288	12,465
Intercompany payables, net	1,200,491	1,168,366
Long-term debt	178,576	177,638
Liabilities, Other than Long-term Debt, Noncurrent	21,889	21,888
Total stockholders' equity	1,838,043	1,928,652
Stockholders' Equity Attributable to Noncontrolling Interest	0	0
Total liabilities and stockholders' equity	3,246,287	3,309,009
WESCO Distribution, Inc.
Condensed Financial Information [Line Items]
Cash and cash equivalents	39,584	32,508	47,452	31,695
Trade accounts receivable, net	0	0
Inventories, net	379,967	373,938
Other current assets	142,241	144,282
Total current assets	561,792	550,728
Intercompany receivables, net	0	0
Property, buildings and equipment, net	56,077	56,735
Intangible assets, net	4,568	4,733
Goodwill and other intangibles, net	246,771	246,771
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	3,751,181	3,828,727
Other assets	12,131	12,844
Total assets	4,632,520	4,700,538
Accounts payable	462,609	445,680
Short-term debt	0	0
Other Liabilities, Current	99,301	113,746
Total current liabilities	561,910	559,426
Intercompany payables, net	626,926	637,849
Long-term debt	686,200	683,407
Liabilities, Other than Long-term Debt, Noncurrent	240,948	232,544
Total stockholders' equity	2,516,536	2,587,312
Stockholders' Equity Attributable to Noncontrolling Interest	0	0
Total liabilities and stockholders' equity	4,632,520	4,700,538
Non-Guarantor Subsidiaries [Member]
Condensed Financial Information [Line Items]
Cash and cash equivalents	114,767	95,811	48,904	92,030
Trade accounts receivable, net	1,082,199	1,117,420
Inventories, net	434,396	445,564
Other current assets	126,746	147,268
Total current assets	1,758,108	1,806,063
Intercompany receivables, net	1,827,417	1,806,215
Property, buildings and equipment, net	117,801	125,990
Intangible assets, net	394,105	425,107
Goodwill and other intangibles, net	1,428,810	1,488,669
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Other assets	34,643	39,167
Total assets	5,560,884	5,691,211
Accounts payable	309,272	319,455
Short-term debt	49,663	46,787
Other Liabilities, Current	117,426	132,204
Total current liabilities	476,361	498,446
Intercompany payables, net	0	0
Long-term debt	472,105	505,385
Liabilities, Other than Long-term Debt, Noncurrent	136,232	141,538
Total stockholders' equity	4,476,911	4,546,329
Stockholders' Equity Attributable to Noncontrolling Interest	725	487
Total liabilities and stockholders' equity	5,560,884	5,691,211
Consolidation, Eliminations [Member]
Condensed Financial Information [Line Items]
Cash and cash equivalents	0	0	0	0
Trade accounts receivable, net	0	0
Inventories, net	0	0
Other current assets	-6,447	-6,465
Total current assets	-6,447	-6,465
Intercompany receivables, net	-1,827,417	-1,806,215
Property, buildings and equipment, net	0	0
Intangible assets, net	0	0
Goodwill and other intangibles, net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	-6,993,447	-7,133,641
Other assets	0	0
Total assets	-8,827,311	-8,946,321
Accounts payable	0	0
Short-term debt	0	0
Other Liabilities, Current	-6,447	-6,465
Total current liabilities	-6,447	-6,465
Intercompany payables, net	-1,827,417	-1,806,215
Long-term debt	0	0
Liabilities, Other than Long-term Debt, Noncurrent	0	0
Total stockholders' equity	-6,993,447	-7,133,641
Stockholders' Equity Attributable to Noncontrolling Interest	0	0
Total liabilities and stockholders' equity	($8,827,311)	($8,946,321)

CONDENSED_CONSOLIDATED_INCOME_

CONDENSED CONSOLIDATED INCOME STATEMENTS (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Information [Line Items]
Net sales	$1,816,330	$1,810,825
Cost of goods sold	1,448,639	1,436,032
Selling, general and administrative expense	264,585	265,462
Depreciation and amortization	15,921	16,372
Affiliate Costs	0	0
Interest expense, net	-20,894	-20,688
Provision for income taxes	19,498	20,416
Net income (loss)	46,793	51,855
Less: Net (loss) income attributable to noncontrolling interest	-238	-50
Net income (loss) attributable to WESCO International, Inc.	47,031	51,905
Comprehensive Income:
Foreign currency translation adjustment	-113,814	-46,500
Comprehensive income attributable to WESCO International, Inc.	-66,783	5,405
Parent Company [Member]
Condensed Financial Information [Line Items]
Net sales	0	0
Cost of goods sold	0	0
Selling, general and administrative expense	8	0
Depreciation and amortization	0	0
Affiliate Costs	51,165	56,210
Interest expense, net	-6,187	-6,070
Provision for income taxes	-1,822	-1,715
Net income (loss)	46,792	51,855
Less: Net (loss) income attributable to noncontrolling interest	0	0
Net income (loss) attributable to WESCO International, Inc.	46,792	51,855
Comprehensive Income:
Foreign currency translation adjustment	-113,814	-46,500
Comprehensive income attributable to WESCO International, Inc.	-67,022	5,355
WESCO Distribution, Inc.
Condensed Financial Information [Line Items]
Net sales	839,282	829,471
Cost of goods sold	669,806	658,584
Selling, general and administrative expense	136,411	136,680
Depreciation and amortization	4,834	4,700
Affiliate Costs	36,268	40,713
Interest expense, net	-18,640	-18,761
Provision for income taxes	2,821	3,047
Net income (loss)	43,038	48,412
Less: Net (loss) income attributable to noncontrolling interest	0	0
Net income (loss) attributable to WESCO International, Inc.	43,038	48,412
Comprehensive Income:
Foreign currency translation adjustment	-113,814	-46,500
Comprehensive income attributable to WESCO International, Inc.	-70,776	1,912
Non-Guarantor Subsidiaries [Member]
Condensed Financial Information [Line Items]
Net sales	1,005,250	1,007,453
Cost of goods sold	807,035	803,547
Selling, general and administrative expense	128,166	128,782
Depreciation and amortization	11,087	11,672
Affiliate Costs	0	0
Interest expense, net	-3,933	-4,143
Provision for income taxes	18,499	19,084
Net income (loss)	44,396	48,511
Less: Net (loss) income attributable to noncontrolling interest	-238	-50
Net income (loss) attributable to WESCO International, Inc.	44,634	48,561
Comprehensive Income:
Foreign currency translation adjustment	-113,814	-46,500
Comprehensive income attributable to WESCO International, Inc.	-69,180	2,061
Consolidation, Eliminations [Member]
Condensed Financial Information [Line Items]
Net sales	-28,202	-26,099
Cost of goods sold	-28,202	-26,099
Selling, general and administrative expense	0	0
Depreciation and amortization	0	0
Affiliate Costs	-87,433	-96,923
Interest expense, net	0	0
Provision for income taxes	0	0
Net income (loss)	-87,433	-96,923
Less: Net (loss) income attributable to noncontrolling interest	0	0
Net income (loss) attributable to WESCO International, Inc.	-87,433	-96,923
Comprehensive Income:
Foreign currency translation adjustment	227,628	93,000
Comprehensive income attributable to WESCO International, Inc.	$140,195	($3,923)

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Information [Line Items]
Payments for (Proceeds from) Other Investing Activities	($785)	($39)
Net cash (used) provided by operating activities	90,056	46,713
Investing Activities:
Capital expenditures	-5,026	-5,012
Acquisition payments	0	-91,187
Net cash used in investing activities	-4,241	-96,160
Financing Activities:
Borrowings	369,299	423,425
Repayments	-388,279	-403,443
Payments for Repurchase of Common Stock	-27,602	-5,331
Proceeds from (Payments for) Other Financing Activities	-7,209	8,888
Net cash used in financing activities	-53,791	23,539
Effect of exchange rate changes on cash and cash equivalents	-5,992	-1,461
Net change in cash and cash equivalents	26,032	-27,369
Cash and cash equivalents at the beginning of period	128,319	123,725
Cash and cash equivalents at the end of period	154,351	96,356
Parent Company [Member]
Condensed Financial Information [Line Items]
Payments for (Proceeds from) Other Investing Activities	0	0
Net cash (used) provided by operating activities	-4,441	-4,871
Investing Activities:
Capital expenditures	0	0
Acquisition payments		0
Net cash used in investing activities	0	0
Financing Activities:
Borrowings	32,125	5,168
Repayments	0	0
Payments for Repurchase of Common Stock	-27,602	-5,331
Proceeds from (Payments for) Other Financing Activities	-82	5,034
Net cash used in financing activities	4,441	4,871
Effect of exchange rate changes on cash and cash equivalents	0	0
Net change in cash and cash equivalents	0	0
Cash and cash equivalents at the beginning of period	0	0
Cash and cash equivalents at the end of period	0	0
WESCO Distribution, Inc.
Condensed Financial Information [Line Items]
Payments for (Proceeds from) Other Investing Activities	32,125	5,169
Net cash (used) provided by operating activities	53,333	20,415
Investing Activities:
Capital expenditures	-4,005	-3,347
Acquisition payments		0
Net cash used in investing activities	-36,130	-8,516
Financing Activities:
Borrowings	218,699	307,851
Repayments	-221,699	-307,851
Payments for Repurchase of Common Stock	0	0
Proceeds from (Payments for) Other Financing Activities	-7,127	3,858
Net cash used in financing activities	-10,127	3,858
Effect of exchange rate changes on cash and cash equivalents	0	0
Net change in cash and cash equivalents	7,076	15,757
Cash and cash equivalents at the beginning of period	32,508	31,695
Cash and cash equivalents at the end of period	39,584	47,452
Non-Guarantor Subsidiaries [Member]
Condensed Financial Information [Line Items]
Payments for (Proceeds from) Other Investing Activities	-785	-39
Net cash (used) provided by operating activities	41,164	31,169
Investing Activities:
Capital expenditures	-1,021	-1,665
Acquisition payments		-91,187
Net cash used in investing activities	-236	-92,813
Financing Activities:
Borrowings	150,600	115,575
Repayments	-166,580	-95,592
Payments for Repurchase of Common Stock	0	0
Proceeds from (Payments for) Other Financing Activities	0	-4
Net cash used in financing activities	-15,980	19,979
Effect of exchange rate changes on cash and cash equivalents	-5,992	-1,461
Net change in cash and cash equivalents	18,956	-43,126
Cash and cash equivalents at the beginning of period	95,811	92,030
Cash and cash equivalents at the end of period	114,767	48,904
Consolidation, Eliminations [Member]
Condensed Financial Information [Line Items]
Payments for (Proceeds from) Other Investing Activities	-32,125	-5,169
Net cash (used) provided by operating activities	0	0
Investing Activities:
Capital expenditures	0	0
Acquisition payments		0
Net cash used in investing activities	32,125	5,169
Financing Activities:
Borrowings	-32,125	-5,169
Repayments	0	0
Payments for Repurchase of Common Stock	0	0
Proceeds from (Payments for) Other Financing Activities	0	0
Net cash used in financing activities	-32,125	-5,169
Effect of exchange rate changes on cash and cash equivalents	0	0
Net change in cash and cash equivalents	0	0
Cash and cash equivalents at the beginning of period	0	0
Cash and cash equivalents at the end of period	0	0
Consolidated Entities [Member]
Financing Activities:
Payments for Repurchase of Common Stock	($27,602)

Subsequent_Events_Details

Subsequent Events (Details) (Hill Country Electric Supply [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Hill Country Electric Supply [Member]
Subsequent Event [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period	$140

Uncategorized_Items

Uncategorized Items	3/31/15
[us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber]	2,190,049