CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 107,637	$ 63,869
Trade accounts receivable, net of allowance for doubtful accounts of $20,811 and $21,590 in 2012 and 2011, respectively	1,020,454	939,422
Other accounts receivable	48,246	43,442
Inventories, net	662,764	626,967
Current deferred income taxes	29,431	28,217
Income taxes receivable	11,284	12,206
Prepaid expenses and other current assets	26,109	23,297
Total current assets	1,905,925	1,737,420
Property, buildings and equipment, net of accumulated depreciation of $189,971 and $190,385 in 2012 and 2011, respectively	140,998	133,550
Intangible assets, net	204,572	156,874
Goodwill	1,127,001	1,008,127
Deferred income taxes	17,926	18,090
Other assets	23,572	24,391
Total assets	3,419,994	3,078,452
Current Liabilities:
Accounts payable	693,177	642,777
Accrued payroll and benefit costs	63,103	76,915
Short-term debt	22,848	3,261
Current portion of long-term debt	2,137	3,150
Bank overdrafts	57,681	47,489
Other current liabilities	71,090	72,254
Total current liabilities	910,036	845,846
Long-term debt, net of discount of $174,485 and $175,908 in 2012 and 2011, respectively	696,758	642,922
Deferred income taxes	244,175	223,005
Other noncurrent liabilities	24,495	20,769
Total liabilities	1,875,464	1,732,542
Stockholders' Equity:
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0	0
Additional capital	1,053,493	1,036,867
Retained earnings	1,066,216	891,789
Treasury stock, at cost; 18,023,348 and 17,936,923 shares in 2012 and 2011, respectively	(600,059)	(593,329)
Accumulated other comprehensive income	24,354	10,057
Total WESCO International stockholders' equity	1,544,622	1,345,998
Noncontrolling interest	(92)	(88)
Total stockholders' equity	1,544,530	1,345,910
Total liabilities and stockholders' equity	3,419,994	3,078,452
Common Stock [Member]
Stockholders' Equity:
Common stock	575	571
Common Class B [Member]
Stockholders' Equity:
Common stock	$ 43	$ 43