Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Net Sales	$ 5,978,861us-gaap_SalesRevenueNet	$ 5,659,141us-gaap_SalesRevenueNet	$ 5,413,281us-gaap_SalesRevenueNet
Cost of merchandise sold	(4,860,314)us-gaap_CostOfGoodsAndServicesSold	(4,614,985)us-gaap_CostOfGoodsAndServicesSold	(4,394,919)us-gaap_CostOfGoodsAndServicesSold
Gross Margin	1,118,547us-gaap_GrossProfit	1,044,156us-gaap_GrossProfit	1,018,362us-gaap_GrossProfit
Selling, general and administrative expenses	(935,132)	(873,415)	(871,374)
Depreciation and amortization	(39,151)	(36,944)	(32,449)
Other income, net	3,918us-gaap_OtherOperatingIncomeExpenseNet	2,495us-gaap_OtherOperatingIncomeExpenseNet	33,143us-gaap_OtherOperatingIncomeExpenseNet
Income from Operations	148,182us-gaap_OperatingIncomeLoss	136,292us-gaap_OperatingIncomeLoss	147,682us-gaap_OperatingIncomeLoss
Interest expense, net	(1,371)us-gaap_InterestExpense	(1,341)us-gaap_InterestExpense	(2,234)us-gaap_InterestExpense
Income before provision for income taxes	146,811	134,951	145,448
Provision for income taxes	(59,125)us-gaap_IncomeTaxExpenseBenefit	(53,677)us-gaap_IncomeTaxExpenseBenefit	(58,850)us-gaap_IncomeTaxExpenseBenefit
Net Income	87,686us-gaap_ProfitLoss	81,274us-gaap_ProfitLoss	86,598us-gaap_ProfitLoss
Net income attributable to noncontrolling interests	(258)	(211)	(307)
Net Income attributable to Graybar Electric Company, Inc.	$ 87,428us-gaap_NetIncomeLoss	$ 81,063us-gaap_NetIncomeLoss	$ 86,291us-gaap_NetIncomeLoss
Net Income attributable to Graybar Electric Company, Inc. per share of Common Stock (usd per share)	$ 5.52us-gaap_EarningsPerShareBasic	$ 5.09us-gaap_EarningsPerShareBasic	$ 5.40us-gaap_EarningsPerShareBasic

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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