Consolidated Statements of Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net Sales		$ 6,110,299	$ 5,978,861	$ 5,659,141
Cost of merchandise sold		(4,955,554)	(4,860,314)	(4,614,985)
Gross Margin		1,154,745	1,118,547	1,044,156
Selling, general and administrative expenses		(965,134)	(935,132)	(873,415)
Depreciation and amortization		(43,242)	(39,151)	(36,944)
Other income, net		8,199	3,918	2,495
Income from Operations		154,568	148,182	136,292
Interest expense, net		(2,227)	(1,371)	(1,341)
Income before provision for income taxes		152,341	146,811	134,951
Provision for income taxes		(61,009)	(59,125)	(53,677)
Net Income		91,332	87,686	81,274
Net income attributable to noncontrolling interests		(264)	(258)	(211)
Net Income attributable to Graybar Electric Company, Inc.		$ 91,068	$ 87,428	$ 81,063
Net Income attributable to Graybar Electric Company, Inc. per share of Common Stock (usd per share)	[1]	$ 5.57	$ 5.38	$ 4.96

[1] (A)Adjusted for the declaration of a 2.5% stock dividend in December 2015, shares related to which were issued in February 2016. Prior to the adjustment, the average common shares outstanding were 15,848 and 15,936 for the years ended December 31, 2014 and 2013, respectively.