Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Net Income	$ 171.6	$ 119.6	$ 472.6	$ 359.1
Other Comprehensive Income (Loss)
Foreign currency translation		(4.3)	(8.9)	6.6
Pension and postretirement benefits liability adjustments (net of tax of $(1.0), $(0.7), $(3.1) and $(1.9) respectively)	3.0	1.8	9.0	5.5
Total Other Comprehensive Income (Loss)	3.0	(2.5)	0.1	12.1
Comprehensive Income	174.6	117.1	472.7	371.2
Less: Comprehensive income attributable to noncontrolling interests, net of tax	0.2	0.2	0.4	1.1
Comprehensive Income attributable to Graybar Electric Company, Inc.	$ 174.4	$ 116.9	$ 472.3	$ 370.1

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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