Condensed Consolidated Statements Of Income - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Condensed Consolidated Statements Of Income [Abstract]
Net Sales		$ 2,979.5	$ 2,852.6	$ 8,717.5	$ 8,317.3
Cost of merchandise sold		(2,382.3)	(2,283.7)	(6,986.5)	(6,640.6)
Gross Margin		597.2	568.9	1,731.0	1,676.7
Selling, general and administrative expenses		(426.8)	(389.6)	(1,235.8)	(1,126.9)
Depreciation and amortization		(20.2)	(18.0)	(59.9)	(47.6)
Other income, net		1.1	1.6	8.7	3.5
Income from Operations		151.3	162.9	444.0	505.7
Non-operating expenses, net		(0.8)	(2.7)	(2.9)	(8.6)
Income before Provision for Income Taxes		150.5	160.2	441.1	497.1
Provision for income taxes		(40.0)	(42.1)	(114.5)	(129.6)
Net Income		110.5	118.1	326.6	367.5
Net income attributable to noncontrolling interests		(0.3)	(0.4)	(0.8)	(0.8)
Net Income attributable to Graybar Electric Company, Inc.		$ 110.2	$ 117.7	$ 325.8	$ 366.7
Net Income attributable to Graybar Electric Company, Inc. per share of Common Stock	[1]	$ 3.42	$ 3.67	$ 10.08	$ 11.40
Cash Dividends per share of Common Stock		$ 0.30	$ 0.30	$ 0.90	$ 0.90
Average Common Shares Outstanding	[1]	32.2	32.1	32.3	32.2

[1] Adjusted for the declaration of a 20% stock dividend in 2023, shares related to which were issued in February 2024. Prior to the adjustment, the average common shares outstanding were 26.7 million and 26.8 million for the three and nine months ended September 30, 2023.