Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net Income	$ 87,686us-gaap_ProfitLoss	$ 81,274us-gaap_ProfitLoss	$ 86,598us-gaap_ProfitLoss
Other Comprehensive Income
Foreign currency translation	(6,643)	(5,553)	1,802
Pension and postretirement benefits liability adjustment (net of tax of $3,477, $(20,270), and $11,735, respectively)	(5,461)	31,838	(18,433)
Total Other Comprehensive Income (Loss)	(12,104)	26,285	(16,631)
Comprehensive Income	75,582	107,559	69,967
Less: comprehensive income (loss) attributable to noncontrolling interests, net of tax	(16)	45	126
Comprehensive Income attributable to Graybar Electric Company, Inc.	$ 75,598us-gaap_ComprehensiveIncomeNetOfTax	$ 107,514us-gaap_ComprehensiveIncomeNetOfTax	$ 69,841us-gaap_ComprehensiveIncomeNetOfTax

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.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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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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