Graybar Electric (GRAYBAR) 10-K 9 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Mar. 01, 2018	Jun. 30, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	GRAYBAR ELECTRIC CO INC
Entity Central Index Key	205,402
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		19,505,812
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 0

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net Sales	$ 6,631,227	$ 6,385,032	$ 6,110,299
Cost of merchandise sold	(5,369,920)	(5,176,669)	(4,955,554)
Gross Margin	1,261,307	1,208,363	1,154,745
Selling, general and administrative expenses	(1,047,157)	(1,008,729)	(965,134)
Depreciation and amortization	(48,890)	(47,852)	(43,242)
Other income, net	6,545	5,347	8,199
Income from Operations	171,805	157,129	154,568
Interest expense, net	(4,257)	(3,630)	(2,227)
Income before Provision for Income Taxes	167,548	153,499	152,341
Provision for income taxes	(95,613)	(60,186)	(61,009)
Net Income	71,935	93,313	91,332
Net income attributable to noncontrolling interests	(327)	(234)	(264)
Net Income attributable to Graybar Electric Company, Inc.	$ 71,608	$ 93,079	$ 91,068
Net Income attributable to Graybar Electric Company, Inc. per share of Common Stock (usd per share)	$ 3.70	$ 4.87	$ 4.82

Consolidated Statements of Inc3

Consolidated Statements of Income Parenthetical - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Stock Dividend	5.00%	2.50%
Average Common Shares Outstanding	17,386	17,183

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 71,935	$ 93,313	$ 91,332
Other Comprehensive Income
Foreign currency translation	5,945	2,218	(13,240)
Pension and postretirement benefits liability adjustment (net of tax of $10,047, $5,245, and $16,261, respectively)	(15,780)	(8,238)	(25,542)
Total Other Comprehensive Loss	(9,835)	(6,020)	(38,782)
Comprehensive Income	62,100	87,293	52,550
Less: comprehensive income (loss) attributable to noncontrolling interests, net of tax	531	379	(276)
Comprehensive Income attributable to Graybar Electric Company, Inc.	$ 61,569	$ 86,914	$ 52,826

Consolidated Statements of Com5

Consolidated Statements of Comprehensive Income Parenthetical - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Pension and postretirement benefits liability adjustment (tax)	$ 10,047	$ 5,245	$ 16,261

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 42,757	$ 43,339
Trade receivables (less allowances of $5,989 and $5,025, respectively)	1,061,590	964,180
Merchandise inventory	579,350	516,732
Other current assets	34,227	24,148
Total Current Assets	1,717,924	1,548,399
Property, at cost
Land	79,787	78,440
Buildings	470,784	454,587
Furniture and fixtures	300,705	286,615
Software	87,313	87,313
Capital leases	25,610	33,652
Total Property, at cost	964,199	940,607
Less – accumulated depreciation and amortization	(539,275)	(512,535)
Net Property	424,924	428,072
Other Non-current Assets	118,509	122,761
Total Assets	2,261,357	2,099,232
Current Liabilities
Short-term borrowings	169,643	140,465
Current portion of long-term debt	2,052	4,155
Trade accounts payable	835,931	752,171
Accrued payroll and benefit costs	119,349	121,421
Other accrued taxes	17,228	16,926
Other current liabilities	78,225	73,028
Total Current Liabilities	1,222,428	1,108,166
Postretirement Benefits Liability	70,747	70,628
Pension Liability	169,225	160,950
Long-term Debt	7,048	7,271
Other Non-current Liabilities	30,361	21,328
Total Liabilities	1,499,809	1,368,343
SHAREHOLDERS’ EQUITY
Outstanding Common Stock	387,687	348,771
Common shares subscribed	18,463	17,929
Less subscriptions receivable	(18,463)	(17,929)
Retained Earnings	619,916	575,380
Accumulated Other Comprehensive Loss	(250,154)	(196,600)
Total Graybar Electric Company, Inc. Shareholders’ Equity	757,449	727,551
Noncontrolling Interests	4,099	3,338
Total Shareholders’ Equity	761,548	730,889
Total Liabilities and Shareholders’ Equity	$ 2,261,357	$ 2,099,232

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 5,989	$ 5,025
Common stock stated value per share (USD per share)	$ 20	$ 20
Authorized	50,000,000	50,000,000
Issued to voting trustees	15,912,467	14,606,830
Issued to shareholders	3,496,114	2,850,551
In treasury, at cost	(24,243)	(18,854)
Outstanding Common Stock	19,384,338	17,438,527
Common Stock, Shares Subscribed	923,156	896,456
Subscripton Receivable	(923,156)	(896,456)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operations
Net Income	$ 71,935	$ 93,313	$ 91,332
Adjustments to reconcile net income to cash provided by operations:
Depreciation and amortization	48,890	47,852	43,242
Deferred income taxes	14,168	19,540	4,173
Net gains on disposal of property	(118)	(1,811)	(5,918)
Net income attributable to noncontrolling interests	(327)	(234)	(264)
Changes in assets and liabilities, net of acquisitions:
Trade receivables	(97,410)	(18,608)	(3,409)
Merchandise inventory	(62,618)	16,503	(54,080)
Other current assets	(10,079)	7,245	10,698
Other non-current assets	(2,459)	1,137	(149)
Trade accounts payable	83,760	(25,534)	36,011
Accrued payroll and benefit costs	(2,072)	9,839	(16,783)
Other current liabilities	9,858	4,303	(14,596)
Other non-current liabilities	(8,400)	(41,345)	6,596
Total adjustments to net income	(26,807)	18,887	5,521
Net cash provided by operations	45,128	112,200	96,853
Cash Flows from Investing Activities
Proceeds from disposal of property	2,166	4,095	15,701
Capital expenditures for property	(41,342)	(35,215)	(74,179)
Acquisition of business, net of cash acquired	0	(59,946)	(18,093)
Net cash used by investing activities	(39,176)	(91,066)	(76,571)
Cash Flows from Financing Activities
Net increase in short-term borrowings	29,178	35,487	38,636
Repayment of long-term debt	0	(1,853)	(3,656)
Principal payments under capital leases	(4,271)	(4,810)	(4,704)
Sales of common stock	17,389	17,007	15,723
Purchases of treasury stock	(13,687)	(11,272)	(14,365)
Sales of noncontrolling interests’ common stock	627	0	401
Purchases of noncontrolling interests’ common stock	(397)	(360)	(109)
Dividends paid	(35,373)	(49,925)	(48,035)
Net cash used by financing activities	(6,534)	(15,726)	(16,109)
Net (Decrease) Increase in Cash	(582)	5,408	4,173
Cash, Beginning of Year	43,339	37,931	33,758
Cash, End of Year	42,757	43,339	37,931
Non-cash Investing and Financing Activities:
Acquisitions of equipment under capital leases	1,945	427	7,354
Cash Paid During the Year for:
Interest, net of amounts capitalized	4,219	3,737	2,024
Income taxes, net of refunds	$ 78,411	$ 36,848	$ 52,076

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Balance at Dec. 31, 2014	$ 681,981	$ 317,199	$ 513,672	$ (152,193)	$ 3,303
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	91,332		91,068		264
Other comprehensive (loss) income	(38,782)			(38,242)	(540)
Stock issued	16,124	15,723			401
Stock purchased	(14,474)	(14,365)			(109)
Dividends declared	(48,035)	7,925	(55,960)
Balance at Dec. 31, 2015	688,146	326,482	548,780	(190,435)	3,319
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	93,313		93,079		234
Other comprehensive (loss) income	(6,020)			(6,165)	145
Stock issued	17,007	17,007
Stock purchased	(11,632)	(11,272)			(360)
Dividends declared	(49,925)	16,554	(66,479)
Balance at Dec. 31, 2016	730,889	348,771	575,380	(196,600)	3,338
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Adoption of ASU 2018-02				0
Net Income	71,935		71,608		327
Other comprehensive (loss) income	(9,835)			(10,039)	204
Stock issued	18,016	17,389			627
Stock purchased	(14,084)	(13,687)			(397)
Dividends declared	(35,373)	35,214	(70,587)
Balance at Dec. 31, 2017	761,548	$ 387,687	619,916	(250,154)	$ 4,099
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Adoption of ASU 2018-02	$ 0		$ 43,515	$ (43,515)

Description of the Business

Description of the Business	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business	DESCRIPTION OF THE BUSINESS Graybar Electric Company, Inc. (“Graybar”, “Company”, "we", "our", or "us") is a New York corporation, incorporated in 1925. We are engaged in the distribution of electrical and communications and data networking products and are a provider of related supply chain management and logistics services. We primarily serve customers in the construction, industrial & utility, and commercial, institutional and government ("CIG") vertical markets, with products and services that support new construction, infrastructure updates, building renovation, facility maintenance, repair and operations ("MRO"), and original equipment manufacturers ("OEM"). We purchase all of the products we sell from others, and we neither manufacture nor contract to manufacture any products we sell. Our business activity is primarily based in the United States (“U.S.”). We also have subsidiary operations with distribution facilities in Canada and Puerto Rico.

Accounting Policies

Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Our accounting policies conform to generally accepted accounting principles in the U.S. ("GAAP”) and are applied on a consistent basis among all years presented. Significant accounting policies are described below. Principles of Consolidation The consolidated financial statements include the accounts of Graybar and its subsidiary companies. All material intercompany balances and transactions have been eliminated. The ownership interests that are held by owners other than the Company in subsidiaries consolidated by the Company are accounted for and reported as noncontrolling interests. Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities. Actual results could differ from these estimates. Reclassifications Certain reclassifications have been made to prior years' financial information to conform to the December 31, 2017 presentation. Subsequent Events We have evaluated subsequent events through the time of the filing of this Annual Report on Form 10-K with the Commission. No material subsequent events have occurred since December 31, 2017 that require recognition or disclosure in our financial statements. Revenue Recognition Revenue is recognized when evidence of a customer arrangement exists, prices are fixed and determinable, product title, ownership and risk of loss transfers to the customer, and collectability is reasonably assured. Revenues recognized are primarily for product sales, but also include freight and handling charges. Our standard shipping terms are FOB shipping point, under which product title passes to the customer at the time of shipment. We also earn revenue for services provided to customers for supply chain management and logistics services. Service revenue, which accounts for less than 1% of net sales, is recognized when services are rendered and completed. Revenue is reported net of all taxes assessed by governmental authorities as a result of revenue-producing transactions, primarily sales tax. Outgoing Freight Expenses We record certain outgoing freight expenses as a component of selling, general and administrative expenses. These costs totaled $ 54,545 , $ 50,949 , and $ 51,100 for the years ended December 31, 2017 , 2016 , and 2015 , respectively. Cash and Cash Equivalents We account for cash on hand, deposits in banks, and other short-term, highly liquid investments with an original maturity of three months or less as cash and cash equivalents. Allowance for Doubtful Accounts We perform ongoing credit evaluations of our customers, and a significant portion of our trade receivables is secured by mechanic’s lien or payment bond rights. We maintain allowances to reflect the expected uncollectability of trade receivables based on past collection history and specific risks identified in the receivables portfolio. Although actual credit losses have historically been within management’s expectations, additional allowances may be required if the financial condition of our customers were to deteriorate. Merchandise Inventory Our inventory is stated at the lower of cost (determined using the last-in, first-out (“LIFO”) cost method) or market. LIFO accounting is a method of accounting that, compared with other inventory accounting methods, generally provides better matching of current costs with current sales. We make provisions for obsolete or excess inventories as necessary to reflect reductions in inventory value. Vendor Allowances Our agreements with many of our suppliers provide for us to earn volume incentives based on purchases during the agreement period. Based on the provisions of our vendor agreements, we develop vendor accrual rates by estimating the point at which we will have completed our performance under the agreement and the deferred amounts will be earned. We perform analyses and review historical trends to ensure the deferred amounts earned are appropriately recorded. Certain vendor agreements contain purchase volume incentives that provide for increased funding when graduated purchase volumes are met. Amounts accrued throughout the year are based on estimates of future activity levels, and could be materially impacted if actual purchase volumes differ. Changes in the estimated amount of incentives are treated as changes in estimate and are recognized in earnings in the period in which the change in estimate occurs. In the event that the operating performance of our suppliers were to decline, however, there can be no assurance that amounts earned would be paid or that the volume incentives would continue to be included in future agreements. Property and Depreciation Property, plant and equipment are recorded at cost. Depreciation is expensed on a straight-line basis over the estimated useful lives of the related assets. Interest costs incurred to finance expenditures for major long-term construction projects are capitalized as part of the asset's historical cost and included in property, plant and equipment, then depreciated over the useful life of the asset. Leasehold improvements are amortized over the term of the lease or the estimated useful life of the improvement, whichever is shorter. Expenditures for maintenance and repairs are charged to expense when incurred, while the costs of significant improvements, which extend the useful life of the underlying asset, are capitalized. Credit Risk Financial instruments that potentially expose us to concentrations of credit risk consist primarily of trade receivables. We perform ongoing credit evaluations of our customers, and a significant portion of our trade receivables may be protected by mechanic’s lien or payment bond rights. We maintain allowances for potential credit losses, and such losses historically have been within management’s expectations. Fair Value We endeavor to utilize the best available information in measuring fair value. GAAP has established a fair value hierarchy, which prioritizes the inputs used in measuring fair value. The tiers in the hierarchy include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own data inputs and assumptions. We have used fair value measurements to value our pension plan assets. Foreign Currency Exchange Rate The functional currency for our Canadian subsidiary is the Canadian dollar. Accordingly, its balance sheet amounts are translated at the exchange rates in effect at the end of each reporting period and its statements of income amounts are translated at the average rates of exchange prevailing during the current period. Currency translation adjustments are included in accumulated other comprehensive loss. Goodwill Our goodwill is not amortized, but rather tested annually for impairment. Goodwill is reviewed annually in the fourth quarter and/or when circumstances or other events might indicate that impairment may have occurred. We first perform a qualitative assessment of goodwill impairment. The qualitative assessment considers several factors including the excess fair value over carrying value as of the last quantitative impairment test, the length of time since the last fair value measurement, the current carrying value, market conditions, actual performance compared to forecasted performance, and the current business outlook. If the qualitative assessment indicates that it is more likely than not that goodwill is impaired, the reporting unit is then quantitatively tested for impairment. If a quantitative assessment is required, the fair value is determined using a variety of assumptions including estimated future cash flows of the reporting unit using applicable discount rates. Definite Lived Intangible Assets The cost of intangible assets with determinable useful lives is amortized to reflect the pattern of economic benefits consumed, either on a straight-line or accelerated basis over the estimated periods benefited. Customer relationships, trade names and other non-contractual intangible assets with determinable lives are amortized over periods generally ranging from 3 to 20 years. Intangible assets are tested for impairment if events or circumstances occur indicating that the respective asset might be impaired. Income Taxes We recognize deferred tax assets and liabilities to reflect the future tax consequences of events that have been recognized in the financial statements or tax returns. Uncertainty exists regarding tax positions taken in previously filed tax returns still subject to examination and positions expected to be taken in future returns. A deferred tax asset or liability results from the temporary difference between an item’s carrying value as reflected in the financial statements and its tax basis, and is calculated using enacted applicable tax rates. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not likely, a valuation allowance is established. Changes in the valuation allowance, when recorded, are included in the provision for income taxes in the consolidated financial statements. We classify interest expense and penalties as part of our provision for income taxes based upon applicable federal and state interest/underpayment percentages. Other Postretirement Benefits We account for postretirement benefits other than pension by accruing the costs of benefits to be provided over the employees’ periods of active service. These costs are determined on an actuarial basis. Our consolidated balance sheets reflect the funded status of postretirement benefits. Pension Plan We sponsor a noncontributory defined benefit pension plan accounted for by accruing the cost to provide the benefits over the employees’ periods of active service. These costs are determined on an actuarial basis. Our consolidated balance sheets reflect the funded status of the defined benefit pension plan. New Accounting Standards No new accounting standards that were issued or became effective during 2017 have had or are expected to have a material impact on our consolidated financial statements except those noted below. In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU" or "Update") No. 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220) ("ASU 2018-02"), which allows entities to reclassify from accumulated other comprehensive income to retained earnings the stranded tax effects resulting from the new federal corporate tax rate enacted in the Tax Cuts and Jobs Act ("TCJA") enacted on December 22, 2017. The ASU will be effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted for reporting periods for which financial statements have not yet been issued or made available for issuance. We elected to early adopt ASU 2018-02 for the annual period ended December 31, 2017; see Note 14 "Accumulated Other Comprehensive Loss" for discussion of our early adoption of the ASU. We are adopting ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), in the first quarter of 2018 using the modified retrospective transition method. The modified retrospective approach requires applying the new revenue standard to all existing contracts not yet completed as of the effective date and recording a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. This will result in a cumulative adjustment to retained earnings of $1,074 effective January 1, 2018. The adjustment reflects the acceleration of revenue and cost related to certain bill and hold transactions. In February 2017, the FASB issued ASU 2017-07, "Compensation - Retirement Benefits (Topic 715)" ("ASU 2017-07"). The changes to the standard require employers to report the service cost component in the same line as other compensation costs arising from services rendered by employees during the reporting period. The other components of net benefit costs will be presented in the income statement separately from the service cost and outside of a subtotal of income from operations. In addition, only the service cost component may be eligible for capitalization where applicable. ASU 2017-07 is effective for interim and annual reporting periods beginning after December 15, 2017. We are currently evaluating the impact ASU 2017-07 will have on our condensed consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” ("ASU 2016-02"). The core principle of Topic 842 requires that a lessee should recognize the assets and liabilities on the balance sheet and disclose key information about leasing arrangements. The amendments in ASU 2016-02 are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. We are currently evaluating the impact the provisions will have on our consolidated financial statements but have decided we will not adopt the guidance early.

Cash Discounts And Doubtful Acc

Cash Discounts And Doubtful Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Cash Discounts and Doubtful Accounts	CASH DISCOUNTS AND DOUBTFUL ACCOUNTS The following table summarizes the activity in the allowances for cash discounts and doubtful accounts: Beginning Balance Provision (Charged to Expense) Deductions Ending Balance For the Year Ended December 31, 2017 Allowance for cash discounts $ 1,731 $ 31,158 $ (30,873 ) $ 2,016 Allowance for doubtful accounts 3,294 3,550 (2,871 ) 3,973 Total $ 5,025 $ 34,708 $ (33,744 ) $ 5,989 For the Year Ended December 31, 2016 Allowance for cash discounts $ 1,736 $ 28,174 $ (28,179 ) $ 1,731 Allowance for doubtful accounts 4,143 2,272 (3,121 ) 3,294 Total $ 5,879 $ 30,446 $ (31,300 ) $ 5,025 For the Year Ended December 31, 2015 Allowance for cash discounts $ 1,764 $ 26,044 $ (26,072 ) $ 1,736 Allowance for doubtful accounts 5,309 2,545 (3,711 ) 4,143 Total $ 7,073 $ 28,589 $ (29,783 ) $ 5,879

Inventory

Inventory	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Inventory	INVENTORY Our inventory is stated at the lower of cost (determined using the LIFO cost method) or market. Inventories valued using the LIFO method comprised 90% of the total inventories at both December 31, 2017 and 2016 . Had the first-in, first-out (“FIFO”) method been used, merchandise inventory would have been $170,885 and $147,091 greater than reported under the LIFO method at December 31, 2017 and 2016 , respectively. In 2017 and 2015 , we did not liquidate any portion of previously-created LIFO layers. In 2016 , we liquidated portions of previously-created LIFO layers, resulting in decreases in cost of merchandise sold of $131 . Reserves for excess and obsolete inventories were $9,220 and $6,553 at December 31, 2017 and 2016 , respectively. The change in the reserve for excess and obsolete inventories, included in cost of merchandise sold, was $2,667 , $1,641 , and $495 for the years ended December 31, 2017 , 2016 , and 2015 , respectively.

Property and Depreciation

Property and Depreciation	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property and Depreciation	PROPERTY AND DEPRECIATION We provide for depreciation and amortization using the straight-line method over the following estimated useful asset lives: Classification Estimated Useful Asset Life Buildings 42 years Leasehold improvements Over the shorter of the asset’s life or the lease term Furniture, fixtures, equipment and software 3 to 14 years Assets held under capital leases Over the shorter of the asset’s life or the lease term Depreciation expense was $38,824 , $39,332 , and $38,588 in 2017 , 2016 , and 2015 , respectively. At the time property is retired or otherwise disposed of, the asset and related accumulated depreciation are removed from the accounts, and any resulting gain or loss is credited or charged to other income, net. Assets held under capital leases, consisting primarily of information technology equipment, are recorded in property with the corresponding obligations carried in long-term debt. The amount capitalized is the present value at the beginning of the lease term of the aggregate future minimum lease payments. Assets held under leases which were capitalized during the year ended December 31, 2017 and 2016 were $1,945 and $427 , respectively. We capitalize interest expense on major construction and development projects while in progress. Interest capitalized in 2017 and 2015 was $44 and $225 , respectively. There was no interest capitalized in 2016 . Where applicable, we will capitalize qualifying internal and external costs incurred to develop or obtain software for internal use during the application development stage. Costs incurred during the pre-application development and post-implementation stages are expensed as incurred. We capitalized software and software development costs of $4,214 and $3,542 in 2017 and 2016 , respectively, and the amounts are recorded in furniture and fixtures. We consider properties to be assets held for sale when all of the following criteria are met: (i) a formal commitment to a plan to sell a property has been made and exercised; (ii) the property is available for sale in its present condition; (iii) actions required to complete the sale of the property have been initiated; (iv) sale of the property is probable and we expect the sale will occur within one year; and (v) the property is being actively marketed for sale at a price that is reasonable given its current market value. Upon designation as an asset held for sale, we record the carrying value of each property at the lower of its carrying value or its estimated fair value, less estimated costs to sell, and depreciation of the property ceases. The net book value of assets held for sale was $464 at December 31, 2016 , and is recorded in net property in the consolidated balance sheet. During 2017 and 2016 , we sold assets classified as held for sale with net book values of $464 and $148 , respectively, and recorded net gains on the assets held for sale of $197 and $2,004 , respectively in other income, net. There are no assets held for sale at December 31, 2017 . We review long-lived assets held and used for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. For assets classified as held and used, impairment may occur if projected undiscounted cash flows are not adequate to cover the carrying value of the assets. In such cases, additional analysis is conducted to determine the amount of the loss to be recognized. The impairment loss is calculated as the difference between the carrying amount of the asset and its estimated fair value. The analysis requires estimates of the amount and timing of projected cash flows and, where applicable, selection of an appropriate discount rate. Such estimates are critical in determining whether any impairment charge should be recorded and the amount of such charge if an impairment loss is deemed necessary. For assets held for sale, impairment occurs whenever the net book value of the property listed for sale exceeds the expected selling price less estimated selling expenses. There were no impairment charges recorded during 2017 and 2016 .

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill The changes in the carrying amount of goodwill, included in other non-current assets in our consolidated balance sheets, for the year ended December 31, 2017 and 2016 , were as follows: 2017 2016 Beginning Balance $ 30,114 $ 13,737 Goodwill Acquired — 16,377 Ending Balance $ 30,114 $ 30,114 In 2016, goodwill increased due to the acquisition of Cape Electrical Supply LLC ("Cape Electric"). See Note 15, "Acquisitions", for further information on our acquisitions. As of December 31, 2017 , we have completed our annual impairment test and concluded that there is no impairment of our goodwill. Other Intangible Assets Other intangible assets, included in other non-current assets in our consolidated balance sheets, consist of the following: As of December 31, 2017 Weighted Average Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships 8.5 to 10.8 years $ 17,163 $ (3,272 ) $ 13,891 Trade name 15 to 20 years 14,263 (1,292 ) 12,971 Non-compete agreements 3 to 5 years 281 (149 ) 132 Other intangible assets 10 years 162 (47 ) 115 Total $ 31,869 $ (4,760 ) $ 27,109 As of December 31, 2016 Weighted Average Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships 8.5 to 10.8 years $ 17,163 $ (1,538 ) $ 15,625 Trade name 15 to 20 years 14,263 (543 ) 13,720 Non-compete agreements 3 to 5 years 281 (84 ) 197 Other intangible assets 10 years 162 (4 ) 158 Total $ 31,869 $ (2,169 ) $ 29,700 In 2016, other intangible assets were acquired in the acquisition of Cape Electric. See Note 15, "Acquisitions", for further information on our acquisitions. Amortization expense for other intangible assets was $2,591 and $1,647 in 2017 and 2016 , respectively. Estimated future amortization expense related to our intangible assets for the years ending December 31 are as follows: 2018 $ 2,579 2019 2,547 2020 2,505 2021 2,493 2022 2,493 After 2022 14,492 $ 27,109 We did not incur impairment losses related to our other intangible assets during the year ended December 31, 2017 .

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES The TCJA was enacted on December 22, 2017. Among the provisions, the TCJA reduces the U.S. federal corporate income tax rate from a maximum of 35% to a flat 21% effective January 1, 2018, requires companies to pay a one-time transition tax on deemed repatriated earnings of certain foreign subsidiaries that were previously tax deferred and creates new taxes on certain foreign sourced earnings. At December 31, 2017 we have not completed our accounting for the tax effects of the enactment of the TCJA. We have made a reasonable estimate of the effects on our existing deferred tax balances and the one-time transition tax under Staff Accounting Bulletin No. 118. For these items for which a reasonable estimate was made, we recognized a provisional amount of $28,840 , which is included as a component of provision for income taxes. Deferred tax assets and liabilities: We remeasured domestic deferred tax assets and liabilities as of December 31, 2017 based on the expected future applicable tax rate. However, we are still analyzing certain aspects of the TCJA and refining our calculations of cumulative timing differences, which could potentially affect the remeasurement of these balances or give rise to new deferred tax amounts. Our calculations could further be impacted by the issuance of future guidance clarifying certain aspects of the TCJA and by state legislative decisions regarding conformity to federal law. U.S. GAAP requires that the effects of tax rate changes be recorded as a component of tax expense from continuing operations in the year of enactment. The provisional amount recorded related to the remeasurement of our deferred tax balances was tax expense of $22,640 , consisting of $43,515 of tax expense related to items previously recorded through accumulated other comprehensive income under FASB Statement No. 158, "Employers' Accounting for Defined Benefit Pension and Other Postretirement Plans - An Amendment of FASB Statements No. 87, 88, 106, and 132(R)" ("FAS 158"), and $20,875 of tax benefit related to items previously recorded through our provision for income taxes. Foreign tax effects: The one-time transition tax is based on our total post-1986 earnings and profits ("E&P") that we previously deferred from U.S. income taxation, and the amount of those earnings held in cash and other specified assets. We have recorded a provisional amount for our one-time transition tax liability, resulting in an increase in income tax expense of $6,200 . We are still finalizing our calculation of the total post-1986 E&P for these foreign subsidiaries and the amounts held in cash and other specified assets, which could change our provisional transition tax liability. Our calculations could further be impacted by the issuance of future guidance clarifying certain aspects of the TCJA and by state legislative decisions regarding conformity to federal law. No additional income taxes have been provided for any outside basis difference inherent in these foreign entities, as these amounts continue to be indefinitely reinvested in foreign operations. We have recorded $1,174 and $5,026 as a current and long-term liability, respectively, as we intend to elect to pay the federal tax over an eight-year period as allowed under the TCJA. The FASB staff commented in January that they believe that Topic 740 is not clear it relates to the accounting for the global intangible low-taxed income (“GILTI”) provisions of the TCJA, and has concluded that an entity may elect to either provide deferred taxes related to GILTI or treat it as a period cost. Given that further guidance is expected surrounding the application of the GILTI rules and the fact that we do not believe GILTI will have a material impact on our tax provision, we have not yet made an accounting policy election as to whether we will provide deferred taxes related to GILTI or treat it as a period cost. We determine our deferred tax assets and liabilities based upon the difference between the financial statement and tax bases of our assets and liabilities calculated using enacted applicable tax rates. We then assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not likely, we establish a valuation allowance. Changes in the valuation allowance, when recorded, are included in the provision for income taxes in the consolidated financial statements. Our unrecognized tax benefits of $ 2,318 , $1,755 , and $2,247 as of December 31, 2017 , 2016 , and 2015 , respectively, are uncertain tax positions that would impact our effective tax rate if recognized. We are periodically engaged in tax return examinations, reviews of statute of limitations periods, and settlements surrounding income taxes. We do not anticipate a material change in unrecognized tax benefits during the next twelve months. Our uncertain tax benefits, and changes thereto, during 2017 , 2016 , and 2015 were as follows: 2017 2016 2015 Balance at January 1, $ 1,755 $ 2,247 $ 3,104 Additions based on tax positions related to current year 437 397 464 Additions based on tax positions of prior years 291 — — Reductions for tax positions of prior years (165 ) (889 ) (252 ) Settlements — — (1,069 ) Balance at December 31, $ 2,318 $ 1,755 $ 2,247 We classify interest expense and penalties as part of our provision for income taxes based upon applicable federal and state interest/underpayment percentages. We have accrued $ 983 and $ 650 in interest and penalties at December 31, 2017 and 2016 , respectively. Interest was computed on the difference between the provision for income taxes recognized in accordance with GAAP and the amount of benefit previously taken or expected to be taken in our federal, state, and local income tax returns. Our federal income tax returns for the tax years 2014 and forward are available for examination by the United States Internal Revenue Service (“IRS”). The statute of limitation for the 2014 federal return will expire on September 15, 2018, unless extended by consent. Our state income tax returns for 2013 through 2017 remain subject to examination by various state authorities with the latest period closing on December 31, 2022. We have not extended the statutes of limitations in any state jurisdictions with respect to years prior to 2013. A reconciliation between the “statutory” federal income tax rate and the effective tax rate in the consolidated statements of income is as follows: For the Years Ended December 31, 2017 2016 2015 “Statutory” federal tax rate 35.0 % 35.0 % 35.0 % State and local income taxes, net of federal benefit 4.0 3.3 3.8 Deemed repatriation of foreign earnings 3.3 — — Effect of tax rate changes 13.5 — — Other, net 1.3 0.9 1.2 Effective tax rate 57.1 % 39.2 % 40.0 % The effective tax rate increased significantly as a result of the remeasurement of deferred tax assets and liabilities and recording the one-time transition tax as a result of the TCJA. As discussed above, a significant portion of the impact of the 2017 "Effect of tax rate changes" relates to items previously recorded through accumulated other comprehensive income under FAS 158. The components of income before taxes and the provision for income taxes recorded in the consolidated statements of income are as follows: For the Years Ended December 31, Components of Income before Taxes 2017 2016 2015 Domestic $ 155,268 $ 143,567 $ 143,144 Foreign 12,280 9,932 9,197 Income before taxes $ 167,548 $ 153,499 $ 152,341 For the Years Ended December 31, Components of Income Tax Provision 2017 2016 2015 Current expense U.S. Federal $ 66,475 $ 33,030 $ 46,174 State 11,396 4,821 7,996 Foreign 3,574 2,795 2,666 Total current expense $ 81,445 $ 40,646 $ 56,836 Deferred expense (benefit) U.S. Federal 15,332 16,676 3,224 State (1,139 ) 3,008 958 Foreign (25 ) (144 ) (9 ) Total deferred expense (benefit) $ 14,168 $ 19,540 $ 4,173 Total income tax provision $ 95,613 $ 60,186 $ 61,009 Federal and state current tax expense was increased by $5,067 and $1,133 , respectively, due to recording the one-time transition tax as a result of the TCJA. Federal deferred tax expense was increased by $22,640 due to the remeasurement of deferred tax assets and liabilities as a result of the TCJA. Deferred income taxes are provided based upon differences between the financial statement and tax bases of assets and liabilities. The following deferred tax assets (liabilities) were recorded at December 31: Assets (Liabilities) 2017 2016 Postretirement benefits $ 19,768 $ 29,788 Payroll accruals 1,866 2,618 Bad debt reserves 1,023 1,322 Other deferred tax assets 4,772 5,251 Pension 37,988 47,847 Inventory 12,123 11,336 Subtotal 77,540 98,162 Less: valuation allowances (23 ) (136 ) Deferred tax assets 77,517 98,026 Fixed assets (27,156 ) (40,887 ) Computer software (3,240 ) (5,724 ) Other deferred tax liabilities (2,622 ) (3,043 ) Deferred tax liabilities (33,018 ) (49,654 ) Net deferred tax assets $ 44,499 $ 48,372 Deferred income taxes included in non-current assets (liabilities) at December 31 were: 2017 2016 Deferred tax assets included in other non-current assets $ 44,860 $ 48,666 Deferred tax liabilities included in other non-current liabilities (361 ) (294 ) Operating loss carryforwards included in net deferred tax assets at December 31 were: 2017 2016 Foreign net operating losses (1) $ 187 $ 239 State net operating losses (2) 504 529 (1) Expires in 2024 (2) Expires between 2023 and 2030 Due to uncertainties regarding the utilization of our state net operating losses, a partial valuation allowance has been applied against the deferred tax benefit at December 31, 2017 . We have no material undistributed earnings of non-U.S. subsidiaries as of December 31, 2017 due to the one-time transition tax enacted under the TCJA. A provision for federal and state income taxes of $5,067 and $1,133 , respectively, has been recorded at December 31, 2017 for this one-time transition tax on undistributed foreign earnings as of December 31, 2017.

Capital Stock

Capital Stock	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Capital Stock	CAPITAL STOCK Our common stock is 100% owned by active and retired employees, and there is no public trading market for our common stock. Since 1928, substantially all of the issued and outstanding shares of common stock have been held of record by voting trustees under successive voting trust agreements. Under applicable New York law, a voting trust may not have a term greater than ten years. Accordingly, a new Voting Trust Agreement was established effective March 3, 2017, which expires by its terms on March 1, 2027 . At December 31, 2017 , approximately 82% of the total shares of common stock was held in the voting trust. The participation of shareholders in the voting trust is voluntary at the time the voting trust is created, but is irrevocable during its term. Shareholders who elect not to participate in the voting trust hold their common stock as shareholders of record. Shareholders may elect to participate in the voting trust at any time during the term of the voting trust. No holder of our common stock or voting trust interests representing our common stock ("common stock", "common shares", or "shares") may sell, transfer or otherwise dispose of any shares without first offering us the option to purchase those shares at the price at which they were issued. Additionally, before the shareholder action described in the next sentence became effective, a shareholder was entitled to any cash dividends accrued for the quarter in which the purchase offer is made, adjusted pro rata for the number of days such shares were held prior to the dividend record date. On June 8, 2017, the shareholders voted to remove this adjustment for accruing dividends on the common stock. We also have the option to purchase at the issue price the common shares of any shareholder who ceases to be an employee for any reason other than death or "retirement" (as defined in our amended restated certificate of incorporation), and on the first anniversary of any holder's death. In the past, we have always exercised these purchase options and we expect to continue to do so in the foreseeable future. However, we can make no assurance that we will continue to exercise our purchase option in the future. All outstanding shares have been issued at $20.00 per share. During 2017 , eligible employees and qualified retirees subscribed for 923,156 shares totaling $18,463 . Subscribers elected to make payments under one of the following options: (i) all shares subscribed for on or before January 5, 2018 ; or (ii) all shares subscribed for in installments paid through payroll deductions (or in certain cases where a subscriber is no longer on our payroll, through direct monthly payments) over an eleven-month period. Common shares were delivered to subscribers as of January 5, 2018 , in the case of shares paid for prior to January 5, 2018 . Shares will be issued and delivered to subscribers on a quarterly basis, as of the tenth day of March, June, September, and December, to the extent full payments for shares are made in the case of subscriptions under the installment method. Shown below is a summary of shares purchased and retired by the Company during the three years ended December 31: Shares of Common Stock Purchased Retired 2017 684,347 678,958 2016 563,590 610,626 2015 718,269 666,861 We also have authorized 10,000,000 shares of Delegated Authority Preferred Stock (“preferred stock”), par value one cent ( $0.01 ). The preferred stock may be issued in one or more series, with the designations, relative rights, preferences, and limitations of shares of each such series being fixed by a resolution of our Board of Directors. There were no shares of preferred stock outstanding at December 31, 2017 and 2016 . On December 13, 2017 , our Board of Directors declared a 10% common stock dividend. Each shareholder was entitled to one share of common stock for every ten shares held as of December 18, 2017 . The stock was issued on February 2, 2018 . On December 8, 2016 , our Board of Directors declared a 5% common stock dividend. Each shareholder was entitled to one share of common stock for every twenty shares held as of December 19, 2016 . The stock was issued on February 3, 2017 . On December 10, 2015, our Board of Directors, declared a 2.5% common stock dividend. Each shareholder was entitled to one share of common stock for every forty shares held as of December 18, 2015. The stock was issued on February 1, 2016.

Net Income Per Share of Common

Net Income Per Share of Common Stock	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Net Income Per Share of Common Stock	NET INCOME PER SHARE OF COMMON STOCK The computation of net income per share of common stock is based on the average number of common shares outstanding during each year, adjusted in all periods presented for the declaration of a 10% stock dividend declared in 2017 , a 5% stock dividend declared in 2016 , and a 2.5% stock dividend declared in 2015 . The average number of shares used in computing net income per share of common stock at December 31, 2017 , 2016 , and 2015 was 19,367,048 , 19,124,547 , and 18,900,929 , respectively.

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	DEBT December 31, Long-term Debt 2017 2016 Capital leases, various maturities, with a weighted average interest rate of 5.97% $ 9,100 $ 11,426 Less current portion (2,052 ) (4,155 ) Long-term Debt $ 7,048 $ 7,271 Long-term Debt matures as follows: 2018 $ 2,052 2019 1,383 2020 1,213 2021 1,162 2022 986 After 2022 2,304 $ 9,100 The carrying amount of our outstanding long-term, fixed-rate debt exceeded its fair value by $737 and $984 at December 31, 2017 and 2016 , respectively. The fair value of the long-term, fixed-rate debt is estimated by calculating future cash flows at interpolated Treasury yields with similar maturities, plus an estimate of our credit risk spread. The fair value of our variable-rate short- and long-term debt approximates its carrying value at December 31, 2017 and 2016 , respectively. Revolving Credit Facility On December 31, 2017 and 2016 , we along with Graybar Canada Limited, our Canadian operating subsidiary (“Graybar Canada”), had an unsecured, five -year, $550,000 revolving credit agreement maturing in June 2019 with Bank of America, N.A. and other lenders named therein (the "Credit Agreement"), which includes a combined letter of credit sub-facility of up to $50,000 , a U.S. swing line loan facility of up to $50,000 , and a Canadian swing line loan facility of up to $20,000 . The Credit Agreement includes a $100,000 sublimit (in U.S. or Canadian dollars) for borrowings by Graybar Canada and contains an accordion feature, which allows us to request increases in the aggregate borrowing commitments of up to $300,000 . Borrowings of Graybar Canada may be in U.S. dollars or Canadian dollars. The obligations of Graybar Canada are secured by the guaranty of Graybar and any material domestic subsidiaries of Graybar (as defined in the Credit Agreement). Under no circumstances will Graybar Canada use its borrowings to benefit Graybar or its operations, including without limitation to repay any of Graybar’s obligations under the facility. Interest on our borrowings under the Credit Agreement are based on, at the borrower’s election, either (A) (i) the base rate (as defined in the Credit Agreement), or (ii) LIBOR (in the case of Graybar as borrower) or (B) (i) the base rate (as defined in the agreement) or (ii) CDOR (in the case of Graybar Canada as borrower), in each case plus an applicable margin, as determined by the pricing grid set forth in the Credit Agreement. In connection with such a borrowing, the applicable borrower also selects the term of the loan, up to six months. Swing line loans, which are daily loans, bear interest at a rate based on, at the borrower’s election, either (i) the base rate or (ii) the daily floating Eurodollar rate (or CDOR, in the case of Graybar Canada as borrower). In addition to interest payments, there are also certain fees and obligations associated with borrowings, swing line loans, letters of credit and other administrative matters. The Credit Agreement provides for a quarterly commitment fee ranging from 0.25% to 0.40% per annum, subject to adjustment based upon the consolidated leverage ratio for a fiscal quarter, and letter of credit fees ranging from 1.00% to 1.60% per annum payable quarterly, subject to such adjustment. Borrowings can be either base rate loans plus a margin ranging from 0.00% to 0.60% or Eurodollar rate loans plus a margin ranging from 1.00% to 1.60% , subject to adjustment based upon our consolidated leverage ratio. Availability under the Credit Agreement is subject to the accuracy of representations and warranties and absence of a default and, in the case of Canadian borrowings denominated in Canadian dollars, the absence of a material adverse change in the national or international financial markets, which would make it impracticable to lend Canadian dollars. The Credit Agreement also provides for customary events of default, including a failure to pay principal, interest or fees when due, the fact that any representation or warranty made by any of the credit parties is materially incorrect, failure to comply with covenants, the occurrence of an event of default under certain other indebtedness by us and our subsidiaries, the commencement of certain insolvency or receivership events affecting any of the credit parties, certain actions under Employee Retirement Income Security Act ("ERISA") and the occurrence of a change in control of any of the credit parties (subject to certain permitted transactions as described in the Credit Agreement). Upon the occurrence of an event of default, the commitments of the lenders may be terminated and all outstanding obligations of the credit parties under the Credit Agreement may be declared immediately due and payable. The Credit Agreement contains customary affirmative and negative covenants for credit facilities of this type, including limitations on us and our subsidiaries with respect to indebtedness, liens, changes in the nature of our business, investments, mergers and acquisitions, issuance of equity securities, dispositions of assets and dissolution of certain subsidiaries, transactions with affiliates, restricted payments (subject to incurrence tests, with certain exceptions), as well as securitizations, factoring transactions, and transactions with sanctioned parties or in violation of certain U.S. or Canadian anti-corruption laws. There are also maximum leverage ratio and minimum interest coverage ratio financial covenants that we are subject to during the term of the Credit Agreement. We were in compliance with all covenants as of December 31, 2017 and 2016 . We had total letters of credit of $5,371 and $5,244 outstanding, of which none were issued under the $550,000 revolving credit facility at December 31, 2017 and December 31, 2016 , respectively. The letters of credit are used primarily to support certain workers' compensation insurance policies. Short-term borrowings of $169,643 and $140,465 outstanding at December 31, 2017 and 2016 , respectively, were drawn under the revolving credit facility. Short-term borrowings outstanding during the years ended December 31, 2017 and 2016 ranged from a minimum of $112,292 and $105,014 to a maximum of $229,782 and $311,506 , respectively. The average daily amount of borrowings outstanding under short-term credit agreements during 2017 and 2016 amounted to approximately $166,000 and $185,000 at weighted-average interest rates of 2.16% and 1.52% , respectively. The weighted-average interest rate for amounts outstanding at December 31, 2017 was 2.60% . At December 31, 2017 , we had available unused committed lines of credit amounting to $380,357 , compared to $409,535 at December 31, 2016 . These lines are available to meet our short-term cash requirements, and certain committed lines of credit have annual fees of up to 40 basis points ( 0.40% ) of the committed lines of credit as of December 31, 2017 and 2016 . Private Placement Shelf Agreements On August 2, 2017, we amended our uncommitted $100,000 private placement shelf agreement with PGIM, Inc. formerly known as Prudential Investment Management, Inc. (the "Prudential Shelf Agreement"). The Prudential Shelf Agreement allows us to issue senior promissory notes to affiliates of Prudential at fixed rate terms to be agreed upon at the time of any issuance during a three-year issuance period ending in August 2020. At December 31, 2017 and 2016 , no notes had been issued under the Prudential Shelf Agreement. On September 22, 2016, we entered into an uncommitted $100,000 private placement shelf agreement (the “MetLife Shelf Agreement”) with Metropolitan Life Insurance Company and MetLife Investment Advisors, LLC and each other affiliate of MetLife that becomes a party to the agreement (collectively, “MetLife”). Subject to the terms and conditions set forth below, the MetLife Shelf Agreement is expected to allow the Company to issue senior promissory notes to MetLife at fixed or floating rate economic terms to be agreed upon at the time of any issuance during a three-year issuance period ending in September 2019. Floating rate note interest rates will be based on London Interbank Offered Rate ("LIBOR") plus a spread. No notes have been issued under the MetLife Shelf Agreement, which ranks equally with the Company’s Credit Agreement and Prudential Shelf Agreement. Under these shelf agreements, the term of each note issuance will be selected by us and will not exceed 12 years and will have such other particular terms as shall be set forth, in the case of any series of notes, in the Confirmation of Acceptance with respect to such series. Any notes issued under the Prudential Shelf Agreement or under the MetLife Shelf Agreement will be guaranteed by our material domestic subsidiaries, if any, as described in the Prudential Shelf Agreement and the MetLife Shelf Agreement. Any future proceeds of any issuance under the facilities will be used for general corporate purposes, including working capital and capital expenditures, to refinance existing indebtedness and/or to fund potential acquisitions. Each shelf agreement contains customary representations and warranties of the Company and the applicable lender. Each shelf agreement also contains customary events of default, including: a failure to pay principal, interest or fees when due; a failure to comply with covenants; the fact that any representation or warranty made by any of the credit parties is incorrect when given; the occurrence of an event of default under the Credit Agreement or certain other indebtedness of us and our subsidiaries; the commencement of certain insolvency or receivership events affecting any of the credit parties; certain actions under ERISA; and the occurrence of a change in control of Graybar (subject to certain permitted transactions as described in the Credit Agreement). All outstanding obligations of Graybar under one or both of these agreements may be declared immediately due and payable upon the occurrence of an event of default. Each shelf agreement contains customary affirmative and negative covenants for facilities of this type, including limitations on us and our subsidiaries with respect to indebtedness, liens, changes in the nature of our business, investments, mergers and acquisitions, issuance of equity securities, dispositions of assets and dissolution of certain subsidiaries, transactions with affiliates, restricted payments (subject to incurrence tests, with certain exceptions), as well as securitizations, factoring transactions, and transactions with sanctioned parties or in violation of certain U.S. or Canadian anti-terrorism laws. There are also maximum leverage ratio and minimum interest coverage ratio financial covenants that we are subject to during the term of the shelf agreements. We were in compliance with all covenants as of December 31, 2017 and 2016 . In addition, we have agreed to a most favored lender clause which is designed to ensure that any notes issued in the future under the Prudential Shelf Agreement and MetLife Shelf Agreement in the future will continue to be of equal ranking with indebtedness under our Credit Agreement.

Pension and Other Postretiremen

Pension and Other Postretirement Benefits	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Pension and Other Postretirement Benefits	PENSION AND OTHER POSTRETIREMENT BENEFITS We have a noncontributory defined benefit pension plan covering substantially all employees first hired prior to July 1, 2015 after the completion of one year of service and 1,000 hours of service. The plan provides retirement benefits based on an employee’s average earnings and years of service. These employees become 100% vested after three years of service, regardless of age. A supplemental benefit plan provides nonqualified pension benefits for compensation in excess of the IRS compensation limits applicable to the plan and otherwise eligible compensation deferred. Our plan funding policy is to make contributions provided that the total annual contributions will not be less than ERISA and the Pension Protection Act of 2006 minimums or greater than the maximum tax-deductible amount, to review the contribution and funding strategy on a regular basis, and to allow discretionary contributions to be made by us from time to time. The assets of the defined benefit pension plan are invested primarily in fixed income investments and equity securities. We pay nonqualified pension benefits when they are due according to the terms of the supplemental benefit plan. We provide certain postretirement healthcare and life insurance benefits to retired employees. Substantially all of our employees hired or rehired prior to 2014 may become eligible for postretirement medical benefits if they reach the age and service requirements of the retiree medical plan and retire on a pension (except a deferred pension) under the defined benefit pension plan. Medical benefits are self-insured and claims are administered through a third party administrator. The cost of coverage is determined based on the annual projected plan costs. The participant's premium or cost is determined based on Company guidelines. Postretirement life insurance benefits are insured through an insurance company. We fund postretirement benefits as incurred, and accordingly, there were no assets held in the postretirement benefits plan at December 31, 2017 and 2016 . The following table sets forth information regarding the funded status of our pension and other postretirement benefits as of December 31, 2017 and 2016 : Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Change in Benefit Obligation: Benefit obligation at beginning of period $ 669,789 $ 634,068 $ 76,576 $ 75,937 Service cost 26,415 25,369 2,327 2,288 Interest cost 27,818 28,263 2,844 3,030 Actuarial loss (gain) 85,618 35,504 (61 ) 889 Benefits paid from plan assets (50,136 ) (50,422 ) — — Benefits paid from Company assets (1,589 ) (1,634 ) (6,427 ) (6,958 ) Plan participants' contributions — — 1,540 1,390 Administrative expenses paid (1,603 ) (1,359 ) — — Benefit Obligation at End of Period 756,312 669,789 76,799 76,576 Change in Plan Assets: Fair value of plan assets at beginning of period 507,287 447,258 — — Actual return on plan assets 69,832 31,810 — — Employer contributions (1) 61,589 81,634 4,887 5,568 Plan participants' contributions — — 1,540 1,390 Benefits paid (1) (51,725 ) (52,056 ) (6,427 ) (6,958 ) Administrative expenses paid (1,603 ) (1,359 ) — — Fair Value of Plan Assets at End of Period 585,380 507,287 — — Unfunded Status $ 170,932 $ 162,502 $ 76,799 $ 76,576 (1) Includes $1,589 and $1,634 paid from our assets for unfunded nonqualified pension benefits in fiscal years 2017 and 2016 , respectively. The accumulated benefit obligation for our defined benefit pension plan was $670,060 and $592,810 at December 31, 2017 and 2016 , respectively. Amounts recognized in the consolidated balance sheet for the years ended December 31 consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Current accrued benefit cost $ 1,707 $ 1,552 $ 6,052 $ 5,948 Non-current accrued benefit cost 169,225 160,950 70,747 70,628 Net amount recognized $ 170,932 $ 162,502 $ 76,799 $ 76,576 Amounts recognized in accumulated other comprehensive loss for the years ended December 31, net of tax, consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Net actuarial loss $ 192,456 $ 177,234 $ 10,575 $ 11,093 Prior service cost (gain) 201 457 (1,195 ) (2,527 ) Accumulated other comprehensive loss $ 192,657 $ 177,691 $ 9,380 $ 8,566 Amounts estimated to be amortized from accumulated other comprehensive loss into net periodic benefit costs in 2018 , net of tax, consist of the following: Pension Benefits Postretirement Benefits Net actuarial loss $ 19,965 $ 613 Prior service cost (gain) 235 (1,453 ) Accumulated other comprehensive loss (income) $ 20,200 $ (840 ) Weighted-average assumptions used to determine the actuarial present value of the pension and postretirement benefit obligations as of December 31 are: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Discount rate 3.67 % 4.15 % 3.44% 3.78% Rate of compensation increase 4.74 % 4.52 % — — Healthcare cost trend on covered charges — — 5.5% / 5% 6% / 5% For measurement of the postretirement benefit obligation, a 5.5% annual rate of increase in the per capita cost of covered healthcare benefits was assumed at December 31, 2017 . This rate is assumed to decline to 5.0% at January 1, 2019 and remain at that level thereafter. A one percent increase or decrease in the assumed healthcare cost trend rate would not have had a material effect on the postretirement benefit obligations as of December 31, 2017 and 2016 . The net periodic benefit cost for the years ended December 31, 2017 , 2016 , and 2015 included the following components: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Service cost $ 26,415 $ 25,369 $ 25,607 $ 2,327 $ 2,288 $ 2,505 Interest cost 27,818 28,263 25,203 2,844 3,030 2,925 Expected return on plan assets (30,631 ) (27,016 ) (28,297 ) — — — Amortization of: Net actuarial loss 21,503 19,164 20,028 788 709 1,044 Prior service cost (gain) 420 423 452 (2,181 ) (2,181 ) (2,181 ) Net periodic benefit cost $ 45,525 $ 46,203 $ 42,993 $ 3,778 $ 3,846 $ 4,293 Weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31 were: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Discount rate 4.15 % 4.48 % 4.08 % 3.78% 4.09% 3.77% Expected return on plan assets 5.75 % 5.75 % 6.25 % — — — Rate of compensation increase 4.52 % 4.44 % 4.47 % — — — Healthcare cost trend on covered charges — — — 6% / 5% 6.5% / 5% 7% / 5% The expected return on plan assets assumption for the defined benefit pension plan is a long-term assumption and was determined after evaluating input from both the plan’s actuary and pension fund investment advisors, consideration of macroeconomic conditions, historical rates of return on plan assets, and anticipated current and long-term rates of return on the various classes of assets in which the plan invests. For measurement of the postretirement benefits net periodic cost, a 6.0% annual rate of increase in per capita cost of covered healthcare benefits was assumed for 2017 . The rate was assumed to decline to 5.0% in 2019 and to remain at that level thereafter. A one percent increase or decrease in the assumed healthcare cost trend rate would not have had a material effect on 2017 , 2016 and 2015 net periodic benefit cost. We expect to contribute $40,000 to our defined benefit pension plan and fund $1,626 for non-qualified pension benefits during 2018 . Estimated future defined benefit pension and other postretirement benefit plan payments to plan participants for the years ending December 31 are as follows: Year Pension Benefits Postretirement Benefits 2018 $ 48,665 $ 6,156 2019 51,270 6,565 2020 52,701 6,856 2021 51,088 7,026 2022 52,146 7,003 After 2022 276,523 33,742 The investment objective of our defined benefit pension plan is to ensure that there are sufficient assets to fund regular pension benefits payable to employees over the long-term life of the plan. Our defined benefit pension plan seeks to allocate plan assets in a manner that is closely duration-matched with the actuarial projected cash flow liabilities, consistent with prudent standards for preservation of capital, tolerance of investment risk, and maintenance of liquidity. Assets of the qualified pension plan are held by Comerica Bank (the "Trustee"). Our defined benefit pension plan utilizes a liability-driven investment (“LDI”) approach to help meet these objectives. The LDI strategy employs a structured fixed-income portfolio designed to reduce volatility in the plan's future funding requirements and funding status. This is accomplished by using a blend of corporate fixed-income securities, long duration government, and quasi-governmental, as well as appropriate levels of equity and alternative investments designed to optimize the plan's liability hedge ratio. In practice, the value of an asset portfolio constructed primarily of fixed income securities is inversely correlated to changes in market interest rates, primarily offsetting changes in the value of the pension benefit obligation caused by changes in the interest rate used to discount plan liabilities. Asset allocation information for the defined benefit pension plan at December 31, 2017 and 2016 is as follows: Investment 2017 Actual Allocation 2017 Target Allocation Range 2016 Actual Allocation 2016 Target Allocation Range Equity securities-U.S. 8 % 3-15% 8 % 3-15% Equity securities-International 10 % 3-15% 11 % 3-15% Fixed income investments-U.S. 70 % 35-75% 62 % 35-75% Fixed income investments-International 3 % 3-10% 5 % 3-10% Absolute return 4 % 5-15% 5 % 5-15% Real assets 3 % 3-10% 3 % 3-10% Private equity 1 % 0-3% 1 % 0-3% Short-term investments 1 % 0-3% 5 % 0-3% Total 100 % 100% 100 % 100% The following is a description of the valuation methodologies used for assets held by the defined benefit pension plan measured at fair value: Equity securities - U.S. Equity securities - U.S. consist of investments in U.S. corporate stocks and U.S. equity mutual funds. U.S. equity mutual funds include publicly traded mutual funds and a bank collective fund for ERISA plans. U.S. corporate stocks and U.S. equity mutual funds are primarily large-capitalization stocks (defined as companies with market capitalization of more than $10 billion). U.S. corporate stocks and publicly traded mutual funds are valued at the closing price reported on the active public market in which the individual securities are traded and are classified as Level 1. The bank collective fund for ERISA plans is valued at the net asset value ("NAV") of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Equity securities - International Equity securities - International consist of investments in international corporate stocks and publicly traded mutual funds and are both primarily investments within developed and emerging markets. Both are valued at the closing price reported on the active public market in which the individual securities are traded and are classified as Level 1. Fixed income investments - U.S. Fixed income investments - U.S. consist of U.S. corporate bonds, government and government agency bonds, as well as a publicly traded mutual fund and commingled funds, both of which invest in corporate and government debt securities within the U.S. U.S. corporate bonds, government and government agency bonds, and the publicly traded mutual fund are valued at the closing price reported on the active market in which they are traded and thus are classified as Level 1. The commingled funds are valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Fixed income investments - International Fixed income investments - International consist of international corporate bonds. International corporate bonds are valued at the closing price reported on the active market in which they are traded and thus are classified as Level 1. Absolute return Absolute return consists of investments in various hedge funds structured as fund-of-funds (defined as a single fund that invests in multiple funds). The hedge funds use various investment strategies in an attempt to generate non-correlated returns. A fund-of-funds is designed to help diversify and reduce the risk of the overall portfolio. The hedge funds are valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Audited financial statements are produced on an annual basis for the hedge funds. Real assets Real assets consists of a natural resource fund (oil, gas and forestry) and a real estate investment trust ("REIT"). The natural resource fund is owned by a limited partnership ("LP"). The LP is generally characterized as requiring a long-term commitment with limited liquidity. The value of the LP is not publicly available and thus, is classified as Level 3. The REIT is a commingled trust. The commingled trust is valued at the NAV of units of the trust. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Audited financial statements are produced on an annual basis for the LP and REIT. Private equity Private equity is an asset class that is generally characterized as requiring long-term commitments and where liquidity is typically limited. Private equity does not have an actively traded market with readily observable prices. The investments are LPs structured as fund-of-funds. The investments are diversified across typical private equity strategies including: buyouts, co-investments, secondary offerings, venture capital, and special situations. Valuations are developed using a variety of proprietary model methodologies. Valuations may be derived from publicly available sources as well as information obtained from each fund's general partner based upon public market conditions and returns. All private equity investments are classified as Level 3. Audited financial statements are produced on an annual basis for the private equity investments. Short-term investments Short-term investments consist of cash and cash equivalents in a short-term fund which is valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. The methods described above may produce fair value calculations that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while we believe our defined benefit pension plan valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date. There have been no changes in the methodologies for determining fair value at December 31, 2017 or 2016 . The following tables set forth, by level within the fair value hierarchy, the defined benefit pension plan assets measured at fair value as of December 31, 2017 and 2016 : December 31, 2017 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 11,488 $ 34,950 $ — $ — $ 46,438 Equity securities - International — 59,632 — — 59,632 Fixed income investments - U.S. 296,232 114,447 — — 410,679 Fixed income investments - International — 17,210 — — 17,210 Absolute return 24,444 — — — 24,444 Real assets 15,565 — — 197 15,762 Private equity — — — 7,461 7,461 Short-term investments 3,754 — — — 3,754 Total $ 351,483 $ 226,239 $ — $ 7,658 $ 585,380 December 31, 2016 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 9,827 $ 30,952 $ — $ — $ 40,779 Equity securities - International — 55,619 — — 55,619 Fixed income investments - U.S. 99,383 218,712 — — 318,095 Fixed income investments - International — 27,346 — — 27,346 Absolute return 25,479 — — — 25,479 Real assets 14,852 — — 195 15,047 Private equity — — — 1,942 1,942 Short-term investments 22,980 — — — 22,980 Total $ 172,521 $ 332,629 $ — $ 2,137 $ 507,287 The tables below set forth a summary of changes in the fair value of the defined benefit pension plan's Level 3 assets for the years ended December 31, 2017 and 2016 : December 31, 2017 Real Assets Private Equity Total Balance, beginning of year $ 195 $ 1,942 $ 2,137 Realized gains — 96 96 Unrealized gains (losses) 2 (100 ) (98 ) Purchases — 6,891 6,891 Sales — (1,368 ) (1,368 ) Balance, end of year $ 197 $ 7,461 $ 7,658 December 31, 2016 Real Assets Private Equity Total Balance, beginning of year $ 456 $ 2,704 $ 3,160 Realized gains 12 181 193 Unrealized losses (19 ) (150 ) (169 ) Purchases — 121 121 Sales (254 ) (914 ) (1,168 ) Balance, end of year $ 195 $ 1,942 $ 2,137

Profit Sharing and Savings Plan

Profit Sharing and Savings Plan	12 Months Ended
	Dec. 31, 2017
Defined Contribution Plan Disclosure [Line Items]
Profit Sharing and Savings Plan	PENSION AND OTHER POSTRETIREMENT BENEFITS We have a noncontributory defined benefit pension plan covering substantially all employees first hired prior to July 1, 2015 after the completion of one year of service and 1,000 hours of service. The plan provides retirement benefits based on an employee’s average earnings and years of service. These employees become 100% vested after three years of service, regardless of age. A supplemental benefit plan provides nonqualified pension benefits for compensation in excess of the IRS compensation limits applicable to the plan and otherwise eligible compensation deferred. Our plan funding policy is to make contributions provided that the total annual contributions will not be less than ERISA and the Pension Protection Act of 2006 minimums or greater than the maximum tax-deductible amount, to review the contribution and funding strategy on a regular basis, and to allow discretionary contributions to be made by us from time to time. The assets of the defined benefit pension plan are invested primarily in fixed income investments and equity securities. We pay nonqualified pension benefits when they are due according to the terms of the supplemental benefit plan. We provide certain postretirement healthcare and life insurance benefits to retired employees. Substantially all of our employees hired or rehired prior to 2014 may become eligible for postretirement medical benefits if they reach the age and service requirements of the retiree medical plan and retire on a pension (except a deferred pension) under the defined benefit pension plan. Medical benefits are self-insured and claims are administered through a third party administrator. The cost of coverage is determined based on the annual projected plan costs. The participant's premium or cost is determined based on Company guidelines. Postretirement life insurance benefits are insured through an insurance company. We fund postretirement benefits as incurred, and accordingly, there were no assets held in the postretirement benefits plan at December 31, 2017 and 2016 . The following table sets forth information regarding the funded status of our pension and other postretirement benefits as of December 31, 2017 and 2016 : Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Change in Benefit Obligation: Benefit obligation at beginning of period $ 669,789 $ 634,068 $ 76,576 $ 75,937 Service cost 26,415 25,369 2,327 2,288 Interest cost 27,818 28,263 2,844 3,030 Actuarial loss (gain) 85,618 35,504 (61 ) 889 Benefits paid from plan assets (50,136 ) (50,422 ) — — Benefits paid from Company assets (1,589 ) (1,634 ) (6,427 ) (6,958 ) Plan participants' contributions — — 1,540 1,390 Administrative expenses paid (1,603 ) (1,359 ) — — Benefit Obligation at End of Period 756,312 669,789 76,799 76,576 Change in Plan Assets: Fair value of plan assets at beginning of period 507,287 447,258 — — Actual return on plan assets 69,832 31,810 — — Employer contributions (1) 61,589 81,634 4,887 5,568 Plan participants' contributions — — 1,540 1,390 Benefits paid (1) (51,725 ) (52,056 ) (6,427 ) (6,958 ) Administrative expenses paid (1,603 ) (1,359 ) — — Fair Value of Plan Assets at End of Period 585,380 507,287 — — Unfunded Status $ 170,932 $ 162,502 $ 76,799 $ 76,576 (1) Includes $1,589 and $1,634 paid from our assets for unfunded nonqualified pension benefits in fiscal years 2017 and 2016 , respectively. The accumulated benefit obligation for our defined benefit pension plan was $670,060 and $592,810 at December 31, 2017 and 2016 , respectively. Amounts recognized in the consolidated balance sheet for the years ended December 31 consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Current accrued benefit cost $ 1,707 $ 1,552 $ 6,052 $ 5,948 Non-current accrued benefit cost 169,225 160,950 70,747 70,628 Net amount recognized $ 170,932 $ 162,502 $ 76,799 $ 76,576 Amounts recognized in accumulated other comprehensive loss for the years ended December 31, net of tax, consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Net actuarial loss $ 192,456 $ 177,234 $ 10,575 $ 11,093 Prior service cost (gain) 201 457 (1,195 ) (2,527 ) Accumulated other comprehensive loss $ 192,657 $ 177,691 $ 9,380 $ 8,566 Amounts estimated to be amortized from accumulated other comprehensive loss into net periodic benefit costs in 2018 , net of tax, consist of the following: Pension Benefits Postretirement Benefits Net actuarial loss $ 19,965 $ 613 Prior service cost (gain) 235 (1,453 ) Accumulated other comprehensive loss (income) $ 20,200 $ (840 ) Weighted-average assumptions used to determine the actuarial present value of the pension and postretirement benefit obligations as of December 31 are: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Discount rate 3.67 % 4.15 % 3.44% 3.78% Rate of compensation increase 4.74 % 4.52 % — — Healthcare cost trend on covered charges — — 5.5% / 5% 6% / 5% For measurement of the postretirement benefit obligation, a 5.5% annual rate of increase in the per capita cost of covered healthcare benefits was assumed at December 31, 2017 . This rate is assumed to decline to 5.0% at January 1, 2019 and remain at that level thereafter. A one percent increase or decrease in the assumed healthcare cost trend rate would not have had a material effect on the postretirement benefit obligations as of December 31, 2017 and 2016 . The net periodic benefit cost for the years ended December 31, 2017 , 2016 , and 2015 included the following components: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Service cost $ 26,415 $ 25,369 $ 25,607 $ 2,327 $ 2,288 $ 2,505 Interest cost 27,818 28,263 25,203 2,844 3,030 2,925 Expected return on plan assets (30,631 ) (27,016 ) (28,297 ) — — — Amortization of: Net actuarial loss 21,503 19,164 20,028 788 709 1,044 Prior service cost (gain) 420 423 452 (2,181 ) (2,181 ) (2,181 ) Net periodic benefit cost $ 45,525 $ 46,203 $ 42,993 $ 3,778 $ 3,846 $ 4,293 Weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31 were: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Discount rate 4.15 % 4.48 % 4.08 % 3.78% 4.09% 3.77% Expected return on plan assets 5.75 % 5.75 % 6.25 % — — — Rate of compensation increase 4.52 % 4.44 % 4.47 % — — — Healthcare cost trend on covered charges — — — 6% / 5% 6.5% / 5% 7% / 5% The expected return on plan assets assumption for the defined benefit pension plan is a long-term assumption and was determined after evaluating input from both the plan’s actuary and pension fund investment advisors, consideration of macroeconomic conditions, historical rates of return on plan assets, and anticipated current and long-term rates of return on the various classes of assets in which the plan invests. For measurement of the postretirement benefits net periodic cost, a 6.0% annual rate of increase in per capita cost of covered healthcare benefits was assumed for 2017 . The rate was assumed to decline to 5.0% in 2019 and to remain at that level thereafter. A one percent increase or decrease in the assumed healthcare cost trend rate would not have had a material effect on 2017 , 2016 and 2015 net periodic benefit cost. We expect to contribute $40,000 to our defined benefit pension plan and fund $1,626 for non-qualified pension benefits during 2018 . Estimated future defined benefit pension and other postretirement benefit plan payments to plan participants for the years ending December 31 are as follows: Year Pension Benefits Postretirement Benefits 2018 $ 48,665 $ 6,156 2019 51,270 6,565 2020 52,701 6,856 2021 51,088 7,026 2022 52,146 7,003 After 2022 276,523 33,742 The investment objective of our defined benefit pension plan is to ensure that there are sufficient assets to fund regular pension benefits payable to employees over the long-term life of the plan. Our defined benefit pension plan seeks to allocate plan assets in a manner that is closely duration-matched with the actuarial projected cash flow liabilities, consistent with prudent standards for preservation of capital, tolerance of investment risk, and maintenance of liquidity. Assets of the qualified pension plan are held by Comerica Bank (the "Trustee"). Our defined benefit pension plan utilizes a liability-driven investment (“LDI”) approach to help meet these objectives. The LDI strategy employs a structured fixed-income portfolio designed to reduce volatility in the plan's future funding requirements and funding status. This is accomplished by using a blend of corporate fixed-income securities, long duration government, and quasi-governmental, as well as appropriate levels of equity and alternative investments designed to optimize the plan's liability hedge ratio. In practice, the value of an asset portfolio constructed primarily of fixed income securities is inversely correlated to changes in market interest rates, primarily offsetting changes in the value of the pension benefit obligation caused by changes in the interest rate used to discount plan liabilities. Asset allocation information for the defined benefit pension plan at December 31, 2017 and 2016 is as follows: Investment 2017 Actual Allocation 2017 Target Allocation Range 2016 Actual Allocation 2016 Target Allocation Range Equity securities-U.S. 8 % 3-15% 8 % 3-15% Equity securities-International 10 % 3-15% 11 % 3-15% Fixed income investments-U.S. 70 % 35-75% 62 % 35-75% Fixed income investments-International 3 % 3-10% 5 % 3-10% Absolute return 4 % 5-15% 5 % 5-15% Real assets 3 % 3-10% 3 % 3-10% Private equity 1 % 0-3% 1 % 0-3% Short-term investments 1 % 0-3% 5 % 0-3% Total 100 % 100% 100 % 100% The following is a description of the valuation methodologies used for assets held by the defined benefit pension plan measured at fair value: Equity securities - U.S. Equity securities - U.S. consist of investments in U.S. corporate stocks and U.S. equity mutual funds. U.S. equity mutual funds include publicly traded mutual funds and a bank collective fund for ERISA plans. U.S. corporate stocks and U.S. equity mutual funds are primarily large-capitalization stocks (defined as companies with market capitalization of more than $10 billion). U.S. corporate stocks and publicly traded mutual funds are valued at the closing price reported on the active public market in which the individual securities are traded and are classified as Level 1. The bank collective fund for ERISA plans is valued at the net asset value ("NAV") of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Equity securities - International Equity securities - International consist of investments in international corporate stocks and publicly traded mutual funds and are both primarily investments within developed and emerging markets. Both are valued at the closing price reported on the active public market in which the individual securities are traded and are classified as Level 1. Fixed income investments - U.S. Fixed income investments - U.S. consist of U.S. corporate bonds, government and government agency bonds, as well as a publicly traded mutual fund and commingled funds, both of which invest in corporate and government debt securities within the U.S. U.S. corporate bonds, government and government agency bonds, and the publicly traded mutual fund are valued at the closing price reported on the active market in which they are traded and thus are classified as Level 1. The commingled funds are valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Fixed income investments - International Fixed income investments - International consist of international corporate bonds. International corporate bonds are valued at the closing price reported on the active market in which they are traded and thus are classified as Level 1. Absolute return Absolute return consists of investments in various hedge funds structured as fund-of-funds (defined as a single fund that invests in multiple funds). The hedge funds use various investment strategies in an attempt to generate non-correlated returns. A fund-of-funds is designed to help diversify and reduce the risk of the overall portfolio. The hedge funds are valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Audited financial statements are produced on an annual basis for the hedge funds. Real assets Real assets consists of a natural resource fund (oil, gas and forestry) and a real estate investment trust ("REIT"). The natural resource fund is owned by a limited partnership ("LP"). The LP is generally characterized as requiring a long-term commitment with limited liquidity. The value of the LP is not publicly available and thus, is classified as Level 3. The REIT is a commingled trust. The commingled trust is valued at the NAV of units of the trust. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. Audited financial statements are produced on an annual basis for the LP and REIT. Private equity Private equity is an asset class that is generally characterized as requiring long-term commitments and where liquidity is typically limited. Private equity does not have an actively traded market with readily observable prices. The investments are LPs structured as fund-of-funds. The investments are diversified across typical private equity strategies including: buyouts, co-investments, secondary offerings, venture capital, and special situations. Valuations are developed using a variety of proprietary model methodologies. Valuations may be derived from publicly available sources as well as information obtained from each fund's general partner based upon public market conditions and returns. All private equity investments are classified as Level 3. Audited financial statements are produced on an annual basis for the private equity investments. Short-term investments Short-term investments consist of cash and cash equivalents in a short-term fund which is valued at the NAV of units of the fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund. The methods described above may produce fair value calculations that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while we believe our defined benefit pension plan valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date. There have been no changes in the methodologies for determining fair value at December 31, 2017 or 2016 . The following tables set forth, by level within the fair value hierarchy, the defined benefit pension plan assets measured at fair value as of December 31, 2017 and 2016 : December 31, 2017 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 11,488 $ 34,950 $ — $ — $ 46,438 Equity securities - International — 59,632 — — 59,632 Fixed income investments - U.S. 296,232 114,447 — — 410,679 Fixed income investments - International — 17,210 — — 17,210 Absolute return 24,444 — — — 24,444 Real assets 15,565 — — 197 15,762 Private equity — — — 7,461 7,461 Short-term investments 3,754 — — — 3,754 Total $ 351,483 $ 226,239 $ — $ 7,658 $ 585,380 December 31, 2016 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 9,827 $ 30,952 $ — $ — $ 40,779 Equity securities - International — 55,619 — — 55,619 Fixed income investments - U.S. 99,383 218,712 — — 318,095 Fixed income investments - International — 27,346 — — 27,346 Absolute return 25,479 — — — 25,479 Real assets 14,852 — — 195 15,047 Private equity — — — 1,942 1,942 Short-term investments 22,980 — — — 22,980 Total $ 172,521 $ 332,629 $ — $ 2,137 $ 507,287 The tables below set forth a summary of changes in the fair value of the defined benefit pension plan's Level 3 assets for the years ended December 31, 2017 and 2016 : December 31, 2017 Real Assets Private Equity Total Balance, beginning of year $ 195 $ 1,942 $ 2,137 Realized gains — 96 96 Unrealized gains (losses) 2 (100 ) (98 ) Purchases — 6,891 6,891 Sales — (1,368 ) (1,368 ) Balance, end of year $ 197 $ 7,461 $ 7,658 December 31, 2016 Real Assets Private Equity Total Balance, beginning of year $ 456 $ 2,704 $ 3,160 Realized gains 12 181 193 Unrealized losses (19 ) (150 ) (169 ) Purchases — 121 121 Sales (254 ) (914 ) (1,168 ) Balance, end of year $ 195 $ 1,942 $ 2,137
Profit Sharing and Savings Plan
Defined Contribution Plan Disclosure [Line Items]
Profit Sharing and Savings Plan	PROFIT SHARING AND SAVINGS PLAN We provide a defined contribution profit sharing and savings plan covering substantially all of our eligible employees with an individual account for each participant. Employees may make voluntary before-tax and/or after-tax contributions to the saving portion of the plan, ranging from 2% to 50% of pay, subject to limitations imposed by federal tax law, ERISA, and the Pension Protection Act of 2006. All employees hired or rehired after July 1, 2015, are eligible to receive a Company matching contribution beginning the first month after the completion of one year of service and 1,000 hours of service. The Company match is equal to 50% of an eligible employee's before-tax or Roth payroll contribution, up to 6% of pay, with a maximum match of 3% . The matching contribution expense recognized by us was $907 and $363 for the years ended December 31, 2017 and 2016 , respectively. Annual contributions made by us to the profit-sharing portion of the plan are determined by the Board of Directors at their discretion, are generally based on the profitability of the Company. Expense recognized by us under the profit-sharing portion of the plan was $43,235 , $41,365 , and $40,020 for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Rental expense was $27,326 , $25,133 , and $22,685 in 2017 , 2016 , and 2015 , respectively. Future minimum rental payments required under operating leases that have either initial or remaining noncancelable lease terms in excess of one year as of December 31, 2017 are as follows: For the Years Ending December 31, Minimum Rental Payments 2018 $ 25,968 2019 20,476 2020 12,985 2021 8,964 2022 5,713 After 2022 10,679 Graybar and our subsidiaries are subject to various claims, disputes, and administrative and legal matters incidental to our past and current business activities. As a result, contingencies arise resulting from an existing condition, situation, or set of circumstances involving an uncertainty as to the realization of a possible loss. Estimated loss contingencies are accrued only if the loss is probable and the amount of the loss can be reasonably estimated. With respect to a particular loss contingency, it may be probable that a loss has occurred but the estimate of the loss is a wide range. If we deem an amount within the range to be a better estimate than any other amount within the range, that amount will be accrued. However, if no amount within the range is a better estimate than any other amount, the minimum amount of the range is accrued. While we believe that none of these claims, disputes, administrative, and legal matters will have a material adverse effect on our financial position, these matters are uncertain and we cannot at this time determine whether the financial impact, if any, of these matters will be material to our results of operations in the period in which such matters are resolved or a better estimate becomes available.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	ACCUMULATED OTHER COMPREHENSIVE LOSS The components of accumulated other comprehensive loss as of December 31 are as follows: 2017 2016 Currency translation $ (4,602 ) $ (10,343 ) Pension liability (192,657 ) (177,691 ) Postretirement benefits liability (9,380 ) (8,566 ) Adoption of ASU 2018-02 (43,515 ) — Accumulated other comprehensive loss $ (250,154 ) $ (196,600 ) We elected to early adopt ASU 2018-02 for the annual period ended December 31, 2017. The applicable tax rate was adjusted in response to the enactment of the TCJA and the corresponding changes in the U.S. federal statutory tax rate resulted in a reclassification of $43,515 from accumulated other comprehensive loss to retained earnings as of December 31, 2017. The following table represents amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2017 and 2016 : 2017 2016 Amortization of Pension and Other Postretirement Benefits Items Amortization of Pension and Other Postretirement Benefits Items Actuarial Losses Recognized Prior Service Costs Recognized Total Actuarial Losses Recognized Prior Service Costs Recognized Total Affected Line in Consolidated Statement of Income: Selling, general and administrative expenses $ 22,291 $ (1,761 ) $ 20,530 $ 19,873 $ (1,758 ) $ 18,115 Tax (benefit) expense (8,671 ) 685 (7,986 ) (7,731 ) 684 (7,047 ) Total reclassifications for the period, net of tax $ 13,620 $ (1,076 ) $ 12,544 $ 12,142 $ (1,074 ) $ 11,068 The following table represents the activity included in accumulated other comprehensive loss for the years ended December 31, 2017 and 2016 : 2017 2016 Foreign Currency Pension and Other Postretirement Benefits Total Foreign Currency Pension and Other Postretirement Benefits Total Beginning balance January 1, $ (10,343 ) $ (186,257 ) $ (196,600 ) $ (12,416 ) $ (178,019 ) $ (190,435 ) Other comprehensive income before reclassifications 5,741 — 5,741 2,073 — 2,073 Amounts reclassified from accumulated other comprehensive loss (net of tax $(7,986) and $(7,047)) — 12,544 12,544 — 11,068 11,068 Actuarial loss, (net of tax $18,033 and $12,292) — (28,324 ) (28,324 ) — (19,306 ) (19,306 ) Net current-period other comprehensive income (loss) 5,741 (15,780 ) (10,039 ) 2,073 (8,238 ) (6,165 ) Adoption of ASU 2018-02 — (43,515 ) (43,515 ) — — — — Ending balance December 31, $ (4,602 ) $ (245,552 ) $ (250,154 ) $ (10,343 ) $ (186,257 ) $ (196,600 )

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS On July 1, 2016, we purchased Cape Electric, a regional distributor serving electrical contractors and large engineering construction firms, as well as industrial, institutional and utility customers, for approximately $59,946 in cash, net of cash acquired. The purchase price allocation resulted in $16,377 and $23,586 of tax deductible goodwill and other intangible assets, respectively. In April 2015, we acquired 100% of the outstanding capital stock of Advantage, which provides control and automation solutions to industrial users, OEMs and system integrators, for $18,093 in cash, net of cash acquired. The purchase price allocation resulted in $7,057 and $8,283 of tax deductible goodwill and other intangible assets, respectively. Since the date of acquisition, Cape Electric and Advantage results are reflected in our consolidated financial statements. Pro forma results of these acquisitions were not material; therefore, they are not presented.

Quarterly Financial Information

Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (Unaudited)	QUARTERLY FINANCIAL INFORMATION (UNAUDITED) The following tables set forth selected quarterly financial data for the years ended December 31, 2017 and 2016 : 2017 For the Quarter Ended March 31, June 30, September 30, December 31, Net sales $ 1,530,571 $ 1,712,880 $ 1,700,843 $ 1,686,933 Gross margin $ 299,829 $ 322,893 $ 321,984 $ 316,601 Net income (loss) attributable to the Company $ 17,681 $ 33,334 $ 29,434 $ (8,841 ) Net income (loss) attributable to the Company per share of common stock (A) $ 0.91 $ 1.72 $ 1.52 $ (0.45 ) (A) All periods adjusted for a 10% stock dividend declared in December 2017 . Prior to these adjustments, the average common shares outstanding for the first, second, third, and fourth quarters of 2017 were 17,620,521 , 17,641,979 , 17,610,573 , and 17,565,590 , respectively. 2016 For the Quarter Ended March 31, June 30, September 30, December 31, Net sales $ 1,465,480 $ 1,630,521 $ 1,689,619 $ 1,599,412 Gross margin $ 279,647 $ 305,599 $ 318,758 $ 304,359 Net income attributable to the Company $ 15,045 $ 25,635 $ 30,129 $ 22,270 Net income attributable to the Company per share of common stock (A) $ 0.79 $ 1.34 $ 1.57 $ 1.17 (A) All periods adjusted for a 10% stock dividend declared in December 2017 and a 5% stock dividend declared in December 2016 . Prior to these adjustments, the average common shares outstanding for the first, second, third, and fourth quarters of 2016 were 16,537,536 , 16,569,408 , 16,573,041 , and 16,558,984 , respectively.

Accounting Policies (Policies)

Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Graybar and its subsidiary companies. All material intercompany balances and transactions have been eliminated. The ownership interests that are held by owners other than the Company in subsidiaries consolidated by the Company are accounted for and reported as noncontrolling interests.
Estimates	Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities. Actual results could differ from these estimates.
Reclassifications	Reclassifications Certain reclassifications have been made to prior years' financial information to conform to the December 31, 2017 presentation.
Subsequent Events	Subsequent Events We have evaluated subsequent events through the time of the filing of this Annual Report on Form 10-K with the Commission. No material subsequent events have occurred since December 31, 2017 that require recognition or disclosure in our financial statements.
Revenue Recognition	Revenue Recognition Revenue is recognized when evidence of a customer arrangement exists, prices are fixed and determinable, product title, ownership and risk of loss transfers to the customer, and collectability is reasonably assured. Revenues recognized are primarily for product sales, but also include freight and handling charges. Our standard shipping terms are FOB shipping point, under which product title passes to the customer at the time of shipment. We also earn revenue for services provided to customers for supply chain management and logistics services. Service revenue, which accounts for less than 1% of net sales, is recognized when services are rendered and completed. Revenue is reported net of all taxes assessed by governmental authorities as a result of revenue-producing transactions, primarily sales tax.
Outgoing Freight Expenses	Outgoing Freight Expenses We record certain outgoing freight expenses as a component of selling, general and administrative expenses. These costs totaled $ 54,545 , $ 50,949 , and $ 51,100 for the years ended December 31, 2017 , 2016 , and 2015 , respectively.
Cash and Cash Equivalents	Cash and Cash Equivalents We account for cash on hand, deposits in banks, and other short-term, highly liquid investments with an original maturity of three months or less as cash and cash equivalents.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts We perform ongoing credit evaluations of our customers, and a significant portion of our trade receivables is secured by mechanic’s lien or payment bond rights. We maintain allowances to reflect the expected uncollectability of trade receivables based on past collection history and specific risks identified in the receivables portfolio. Although actual credit losses have historically been within management’s expectations, additional allowances may be required if the financial condition of our customers were to deteriorate.
Merchandise Inventory	Merchandise Inventory Our inventory is stated at the lower of cost (determined using the last-in, first-out (“LIFO”) cost method) or market. LIFO accounting is a method of accounting that, compared with other inventory accounting methods, generally provides better matching of current costs with current sales. We make provisions for obsolete or excess inventories as necessary to reflect reductions in inventory value.
Vendor Allowances	Vendor Allowances Our agreements with many of our suppliers provide for us to earn volume incentives based on purchases during the agreement period. Based on the provisions of our vendor agreements, we develop vendor accrual rates by estimating the point at which we will have completed our performance under the agreement and the deferred amounts will be earned. We perform analyses and review historical trends to ensure the deferred amounts earned are appropriately recorded. Certain vendor agreements contain purchase volume incentives that provide for increased funding when graduated purchase volumes are met. Amounts accrued throughout the year are based on estimates of future activity levels, and could be materially impacted if actual purchase volumes differ. Changes in the estimated amount of incentives are treated as changes in estimate and are recognized in earnings in the period in which the change in estimate occurs. In the event that the operating performance of our suppliers were to decline, however, there can be no assurance that amounts earned would be paid or that the volume incentives would continue to be included in future agreements.
Property and Depreciation	Property and Depreciation Property, plant and equipment are recorded at cost. Depreciation is expensed on a straight-line basis over the estimated useful lives of the related assets. Interest costs incurred to finance expenditures for major long-term construction projects are capitalized as part of the asset's historical cost and included in property, plant and equipment, then depreciated over the useful life of the asset. Leasehold improvements are amortized over the term of the lease or the estimated useful life of the improvement, whichever is shorter. Expenditures for maintenance and repairs are charged to expense when incurred, while the costs of significant improvements, which extend the useful life of the underlying asset, are capitalized.
Credit Risk	Credit Risk Financial instruments that potentially expose us to concentrations of credit risk consist primarily of trade receivables. We perform ongoing credit evaluations of our customers, and a significant portion of our trade receivables may be protected by mechanic’s lien or payment bond rights. We maintain allowances for potential credit losses, and such losses historically have been within management’s expectations.
Fair Value	Fair Value We endeavor to utilize the best available information in measuring fair value. GAAP has established a fair value hierarchy, which prioritizes the inputs used in measuring fair value. The tiers in the hierarchy include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own data inputs and assumptions. We have used fair value measurements to value our pension plan assets.
Foreign Currency Exchange Rate	Foreign Currency Exchange Rate The functional currency for our Canadian subsidiary is the Canadian dollar. Accordingly, its balance sheet amounts are translated at the exchange rates in effect at the end of each reporting period and its statements of income amounts are translated at the average rates of exchange prevailing during the current period. Currency translation adjustments are included in accumulated other comprehensive loss.
Goodwill	Goodwill Our goodwill is not amortized, but rather tested annually for impairment. Goodwill is reviewed annually in the fourth quarter and/or when circumstances or other events might indicate that impairment may have occurred. We first perform a qualitative assessment of goodwill impairment. The qualitative assessment considers several factors including the excess fair value over carrying value as of the last quantitative impairment test, the length of time since the last fair value measurement, the current carrying value, market conditions, actual performance compared to forecasted performance, and the current business outlook. If the qualitative assessment indicates that it is more likely than not that goodwill is impaired, the reporting unit is then quantitatively tested for impairment. If a quantitative assessment is required, the fair value is determined using a variety of assumptions including estimated future cash flows of the reporting unit using applicable discount rates.
Definite Lived Intangible Assets	Definite Lived Intangible Assets The cost of intangible assets with determinable useful lives is amortized to reflect the pattern of economic benefits consumed, either on a straight-line or accelerated basis over the estimated periods benefited. Customer relationships, trade names and other non-contractual intangible assets with determinable lives are amortized over periods generally ranging from 3 to 20 years. Intangible assets are tested for impairment if events or circumstances occur indicating that the respective asset might be impaired.
Income Taxes	Income Taxes We recognize deferred tax assets and liabilities to reflect the future tax consequences of events that have been recognized in the financial statements or tax returns. Uncertainty exists regarding tax positions taken in previously filed tax returns still subject to examination and positions expected to be taken in future returns. A deferred tax asset or liability results from the temporary difference between an item’s carrying value as reflected in the financial statements and its tax basis, and is calculated using enacted applicable tax rates. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not likely, a valuation allowance is established. Changes in the valuation allowance, when recorded, are included in the provision for income taxes in the consolidated financial statements. We classify interest expense and penalties as part of our provision for income taxes based upon applicable federal and state interest/underpayment percentages.
Other Postretirement Benefits	Other Postretirement Benefits We account for postretirement benefits other than pension by accruing the costs of benefits to be provided over the employees’ periods of active service. These costs are determined on an actuarial basis. Our consolidated balance sheets reflect the funded status of postretirement benefits.
Pension Plan	Pension Plan We sponsor a noncontributory defined benefit pension plan accounted for by accruing the cost to provide the benefits over the employees’ periods of active service. These costs are determined on an actuarial basis. Our consolidated balance sheets reflect the funded status of the defined benefit pension plan.
New Accounting Standards	New Accounting Standards No new accounting standards that were issued or became effective during 2017 have had or are expected to have a material impact on our consolidated financial statements except those noted below. In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU" or "Update") No. 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220) ("ASU 2018-02"), which allows entities to reclassify from accumulated other comprehensive income to retained earnings the stranded tax effects resulting from the new federal corporate tax rate enacted in the Tax Cuts and Jobs Act ("TCJA") enacted on December 22, 2017. The ASU will be effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted for reporting periods for which financial statements have not yet been issued or made available for issuance. We elected to early adopt ASU 2018-02 for the annual period ended December 31, 2017; see Note 14 "Accumulated Other Comprehensive Loss" for discussion of our early adoption of the ASU. We are adopting ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), in the first quarter of 2018 using the modified retrospective transition method. The modified retrospective approach requires applying the new revenue standard to all existing contracts not yet completed as of the effective date and recording a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. This will result in a cumulative adjustment to retained earnings of $1,074 effective January 1, 2018. The adjustment reflects the acceleration of revenue and cost related to certain bill and hold transactions. In February 2017, the FASB issued ASU 2017-07, "Compensation - Retirement Benefits (Topic 715)" ("ASU 2017-07"). The changes to the standard require employers to report the service cost component in the same line as other compensation costs arising from services rendered by employees during the reporting period. The other components of net benefit costs will be presented in the income statement separately from the service cost and outside of a subtotal of income from operations. In addition, only the service cost component may be eligible for capitalization where applicable. ASU 2017-07 is effective for interim and annual reporting periods beginning after December 15, 2017. We are currently evaluating the impact ASU 2017-07 will have on our condensed consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” ("ASU 2016-02"). The core principle of Topic 842 requires that a lessee should recognize the assets and liabilities on the balance sheet and disclose key information about leasing arrangements. The amendments in ASU 2016-02 are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. We are currently evaluating the impact the provisions will have on our consolidated financial statements but have decided we will not adopt the guidance early.

Cash Discounts And Doubtful A27

Cash Discounts And Doubtful Accounts (Tables)	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Schedule of Cash Discounts and Doubtful Accounts	The following table summarizes the activity in the allowances for cash discounts and doubtful accounts: Beginning Balance Provision (Charged to Expense) Deductions Ending Balance For the Year Ended December 31, 2017 Allowance for cash discounts $ 1,731 $ 31,158 $ (30,873 ) $ 2,016 Allowance for doubtful accounts 3,294 3,550 (2,871 ) 3,973 Total $ 5,025 $ 34,708 $ (33,744 ) $ 5,989 For the Year Ended December 31, 2016 Allowance for cash discounts $ 1,736 $ 28,174 $ (28,179 ) $ 1,731 Allowance for doubtful accounts 4,143 2,272 (3,121 ) 3,294 Total $ 5,879 $ 30,446 $ (31,300 ) $ 5,025 For the Year Ended December 31, 2015 Allowance for cash discounts $ 1,764 $ 26,044 $ (26,072 ) $ 1,736 Allowance for doubtful accounts 5,309 2,545 (3,711 ) 4,143 Total $ 7,073 $ 28,589 $ (29,783 ) $ 5,879

Property and Depreciation (Tabl

Property and Depreciation (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property and Depreciation	We provide for depreciation and amortization using the straight-line method over the following estimated useful asset lives: Classification Estimated Useful Asset Life Buildings 42 years Leasehold improvements Over the shorter of the asset’s life or the lease term Furniture, fixtures, equipment and software 3 to 14 years Assets held under capital leases Over the shorter of the asset’s life or the lease term

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The changes in the carrying amount of goodwill, included in other non-current assets in our consolidated balance sheets, for the year ended December 31, 2017 and 2016 , were as follows: 2017 2016 Beginning Balance $ 30,114 $ 13,737 Goodwill Acquired — 16,377 Ending Balance $ 30,114 $ 30,114
Schedule of Finite-Lived Intangible Assets	Other intangible assets, included in other non-current assets in our consolidated balance sheets, consist of the following: As of December 31, 2017 Weighted Average Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships 8.5 to 10.8 years $ 17,163 $ (3,272 ) $ 13,891 Trade name 15 to 20 years 14,263 (1,292 ) 12,971 Non-compete agreements 3 to 5 years 281 (149 ) 132 Other intangible assets 10 years 162 (47 ) 115 Total $ 31,869 $ (4,760 ) $ 27,109 As of December 31, 2016 Weighted Average Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships 8.5 to 10.8 years $ 17,163 $ (1,538 ) $ 15,625 Trade name 15 to 20 years 14,263 (543 ) 13,720 Non-compete agreements 3 to 5 years 281 (84 ) 197 Other intangible assets 10 years 162 (4 ) 158 Total $ 31,869 $ (2,169 ) $ 29,700
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Estimated future amortization expense related to our intangible assets for the years ending December 31 are as follows: 2018 $ 2,579 2019 2,547 2020 2,505 2021 2,493 2022 2,493 After 2022 14,492 $ 27,109

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Schedule of Unrecognized Tax Benefits Roll Forward	Our uncertain tax benefits, and changes thereto, during 2017 , 2016 , and 2015 were as follows: 2017 2016 2015 Balance at January 1, $ 1,755 $ 2,247 $ 3,104 Additions based on tax positions related to current year 437 397 464 Additions based on tax positions of prior years 291 — — Reductions for tax positions of prior years (165 ) (889 ) (252 ) Settlements — — (1,069 ) Balance at December 31, $ 2,318 $ 1,755 $ 2,247
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation between the “statutory” federal income tax rate and the effective tax rate in the consolidated statements of income is as follows: For the Years Ended December 31, 2017 2016 2015 “Statutory” federal tax rate 35.0 % 35.0 % 35.0 % State and local income taxes, net of federal benefit 4.0 3.3 3.8 Deemed repatriation of foreign earnings 3.3 — — Effect of tax rate changes 13.5 — — Other, net 1.3 0.9 1.2 Effective tax rate 57.1 % 39.2 % 40.0 %
Schedule of Income before Income Tax, Domestic and Foreign	The components of income before taxes and the provision for income taxes recorded in the consolidated statements of income are as follows: For the Years Ended December 31, Components of Income before Taxes 2017 2016 2015 Domestic $ 155,268 $ 143,567 $ 143,144 Foreign 12,280 9,932 9,197 Income before taxes $ 167,548 $ 153,499 $ 152,341
Schedule of Components of Income Tax Expense Benefit	For the Years Ended December 31, Components of Income Tax Provision 2017 2016 2015 Current expense U.S. Federal $ 66,475 $ 33,030 $ 46,174 State 11,396 4,821 7,996 Foreign 3,574 2,795 2,666 Total current expense $ 81,445 $ 40,646 $ 56,836 Deferred expense (benefit) U.S. Federal 15,332 16,676 3,224 State (1,139 ) 3,008 958 Foreign (25 ) (144 ) (9 ) Total deferred expense (benefit) $ 14,168 $ 19,540 $ 4,173 Total income tax provision $ 95,613 $ 60,186 $ 61,009
Schedule of Deferred Tax Assets and Liabilities	The following deferred tax assets (liabilities) were recorded at December 31: Assets (Liabilities) 2017 2016 Postretirement benefits $ 19,768 $ 29,788 Payroll accruals 1,866 2,618 Bad debt reserves 1,023 1,322 Other deferred tax assets 4,772 5,251 Pension 37,988 47,847 Inventory 12,123 11,336 Subtotal 77,540 98,162 Less: valuation allowances (23 ) (136 ) Deferred tax assets 77,517 98,026 Fixed assets (27,156 ) (40,887 ) Computer software (3,240 ) (5,724 ) Other deferred tax liabilities (2,622 ) (3,043 ) Deferred tax liabilities (33,018 ) (49,654 ) Net deferred tax assets $ 44,499 $ 48,372 Deferred income taxes included in non-current assets (liabilities) at December 31 were: 2017 2016 Deferred tax assets included in other non-current assets $ 44,860 $ 48,666 Deferred tax liabilities included in other non-current liabilities (361 ) (294 )
Summary of Operating Loss Carryforwards	Operating loss carryforwards included in net deferred tax assets at December 31 were: 2017 2016 Foreign net operating losses (1) $ 187 $ 239 State net operating losses (2) 504 529 (1) Expires in 2024 (2) Expires between 2023 and 2030

Capital Stock (Tables)

Capital Stock (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of Common Stock Shares Purchased and Retired	Shown below is a summary of shares purchased and retired by the Company during the three years ended December 31: Shares of Common Stock Purchased Retired 2017 684,347 678,958 2016 563,590 610,626 2015 718,269 666,861

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Long-term Debt	December 31, Long-term Debt 2017 2016 Capital leases, various maturities, with a weighted average interest rate of 5.97% $ 9,100 $ 11,426 Less current portion (2,052 ) (4,155 ) Long-term Debt $ 7,048 $ 7,271
Schedule of Long-term Debt Maturities	Long-term Debt matures as follows: 2018 $ 2,052 2019 1,383 2020 1,213 2021 1,162 2022 986 After 2022 2,304 $ 9,100

Pension and Other Postretirem33

Pension and Other Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Schedule of Net Funded Status	The following table sets forth information regarding the funded status of our pension and other postretirement benefits as of December 31, 2017 and 2016 : Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Change in Benefit Obligation: Benefit obligation at beginning of period $ 669,789 $ 634,068 $ 76,576 $ 75,937 Service cost 26,415 25,369 2,327 2,288 Interest cost 27,818 28,263 2,844 3,030 Actuarial loss (gain) 85,618 35,504 (61 ) 889 Benefits paid from plan assets (50,136 ) (50,422 ) — — Benefits paid from Company assets (1,589 ) (1,634 ) (6,427 ) (6,958 ) Plan participants' contributions — — 1,540 1,390 Administrative expenses paid (1,603 ) (1,359 ) — — Benefit Obligation at End of Period 756,312 669,789 76,799 76,576 Change in Plan Assets: Fair value of plan assets at beginning of period 507,287 447,258 — — Actual return on plan assets 69,832 31,810 — — Employer contributions (1) 61,589 81,634 4,887 5,568 Plan participants' contributions — — 1,540 1,390 Benefits paid (1) (51,725 ) (52,056 ) (6,427 ) (6,958 ) Administrative expenses paid (1,603 ) (1,359 ) — — Fair Value of Plan Assets at End of Period 585,380 507,287 — — Unfunded Status $ 170,932 $ 162,502 $ 76,799 $ 76,576 (1) Includes $1,589 and $1,634 paid from our assets for unfunded nonqualified pension benefits in fiscal years 2017 and 2016 , respectively.
Schedule of Amounts Recognized in Balance Sheet	Amounts recognized in the consolidated balance sheet for the years ended December 31 consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Current accrued benefit cost $ 1,707 $ 1,552 $ 6,052 $ 5,948 Non-current accrued benefit cost 169,225 160,950 70,747 70,628 Net amount recognized $ 170,932 $ 162,502 $ 76,799 $ 76,576
Schedule of Amounts Recognized in Accumulated Other Comprensive Income (Loss)	Amounts recognized in accumulated other comprehensive loss for the years ended December 31, net of tax, consist of the following: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Net actuarial loss $ 192,456 $ 177,234 $ 10,575 $ 11,093 Prior service cost (gain) 201 457 (1,195 ) (2,527 ) Accumulated other comprehensive loss $ 192,657 $ 177,691 $ 9,380 $ 8,566
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year	Amounts estimated to be amortized from accumulated other comprehensive loss into net periodic benefit costs in 2018 , net of tax, consist of the following: Pension Benefits Postretirement Benefits Net actuarial loss $ 19,965 $ 613 Prior service cost (gain) 235 (1,453 ) Accumulated other comprehensive loss (income) $ 20,200 $ (840 )
Schedule of Assumptions Used	Weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31 were: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Discount rate 4.15 % 4.48 % 4.08 % 3.78% 4.09% 3.77% Expected return on plan assets 5.75 % 5.75 % 6.25 % — — — Rate of compensation increase 4.52 % 4.44 % 4.47 % — — — Healthcare cost trend on covered charges — — — 6% / 5% 6.5% / 5% 7% / 5% Weighted-average assumptions used to determine the actuarial present value of the pension and postretirement benefit obligations as of December 31 are: Pension Benefits Postretirement Benefits 2017 2016 2017 2016 Discount rate 3.67 % 4.15 % 3.44% 3.78% Rate of compensation increase 4.74 % 4.52 % — — Healthcare cost trend on covered charges — — 5.5% / 5% 6% / 5%
Schedule of Net Periodic Benefit Costs	The net periodic benefit cost for the years ended December 31, 2017 , 2016 , and 2015 included the following components: Pension Benefits Postretirement Benefits 2017 2016 2015 2017 2016 2015 Service cost $ 26,415 $ 25,369 $ 25,607 $ 2,327 $ 2,288 $ 2,505 Interest cost 27,818 28,263 25,203 2,844 3,030 2,925 Expected return on plan assets (30,631 ) (27,016 ) (28,297 ) — — — Amortization of: Net actuarial loss 21,503 19,164 20,028 788 709 1,044 Prior service cost (gain) 420 423 452 (2,181 ) (2,181 ) (2,181 ) Net periodic benefit cost $ 45,525 $ 46,203 $ 42,993 $ 3,778 $ 3,846 $ 4,293
Schedule of Expected Benefit Payments	Estimated future defined benefit pension and other postretirement benefit plan payments to plan participants for the years ending December 31 are as follows: Year Pension Benefits Postretirement Benefits 2018 $ 48,665 $ 6,156 2019 51,270 6,565 2020 52,701 6,856 2021 51,088 7,026 2022 52,146 7,003 After 2022 276,523 33,742
Schedule of Allocation of Plan Assets	Asset allocation information for the defined benefit pension plan at December 31, 2017 and 2016 is as follows: Investment 2017 Actual Allocation 2017 Target Allocation Range 2016 Actual Allocation 2016 Target Allocation Range Equity securities-U.S. 8 % 3-15% 8 % 3-15% Equity securities-International 10 % 3-15% 11 % 3-15% Fixed income investments-U.S. 70 % 35-75% 62 % 35-75% Fixed income investments-International 3 % 3-10% 5 % 3-10% Absolute return 4 % 5-15% 5 % 5-15% Real assets 3 % 3-10% 3 % 3-10% Private equity 1 % 0-3% 1 % 0-3% Short-term investments 1 % 0-3% 5 % 0-3% Total 100 % 100% 100 % 100% The following tables set forth, by level within the fair value hierarchy, the defined benefit pension plan assets measured at fair value as of December 31, 2017 and 2016 : December 31, 2017 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 11,488 $ 34,950 $ — $ — $ 46,438 Equity securities - International — 59,632 — — 59,632 Fixed income investments - U.S. 296,232 114,447 — — 410,679 Fixed income investments - International — 17,210 — — 17,210 Absolute return 24,444 — — — 24,444 Real assets 15,565 — — 197 15,762 Private equity — — — 7,461 7,461 Short-term investments 3,754 — — — 3,754 Total $ 351,483 $ 226,239 $ — $ 7,658 $ 585,380 December 31, 2016 Investment Investments Measured at NAV Level 1 Level 2 Level 3 Total Equity securities - U.S. $ 9,827 $ 30,952 $ — $ — $ 40,779 Equity securities - International — 55,619 — — 55,619 Fixed income investments - U.S. 99,383 218,712 — — 318,095 Fixed income investments - International — 27,346 — — 27,346 Absolute return 25,479 — — — 25,479 Real assets 14,852 — — 195 15,047 Private equity — — — 1,942 1,942 Short-term investments 22,980 — — — 22,980 Total $ 172,521 $ 332,629 $ — $ 2,137 $ 507,287
Schedule of Changes in Fair Value of Plan Assets	The tables below set forth a summary of changes in the fair value of the defined benefit pension plan's Level 3 assets for the years ended December 31, 2017 and 2016 : December 31, 2017 Real Assets Private Equity Total Balance, beginning of year $ 195 $ 1,942 $ 2,137 Realized gains — 96 96 Unrealized gains (losses) 2 (100 ) (98 ) Purchases — 6,891 6,891 Sales — (1,368 ) (1,368 ) Balance, end of year $ 197 $ 7,461 $ 7,658 December 31, 2016 Real Assets Private Equity Total Balance, beginning of year $ 456 $ 2,704 $ 3,160 Realized gains 12 181 193 Unrealized losses (19 ) (150 ) (169 ) Purchases — 121 121 Sales (254 ) (914 ) (1,168 ) Balance, end of year $ 195 $ 1,942 $ 2,137

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	Future minimum rental payments required under operating leases that have either initial or remaining noncancelable lease terms in excess of one year as of December 31, 2017 are as follows: For the Years Ending December 31, Minimum Rental Payments 2018 $ 25,968 2019 20,476 2020 12,985 2021 8,964 2022 5,713 After 2022 10,679

Accumulated Other Comprehensi35

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Components of Accumulated Other Comprehensive Income (Loss)	The components of accumulated other comprehensive loss as of December 31 are as follows: 2017 2016 Currency translation $ (4,602 ) $ (10,343 ) Pension liability (192,657 ) (177,691 ) Postretirement benefits liability (9,380 ) (8,566 ) Adoption of ASU 2018-02 (43,515 ) — Accumulated other comprehensive loss $ (250,154 ) $ (196,600 )
Reclassification out of Accumulated Other Comprehensive Income (Loss)	The following table represents amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2017 and 2016 : 2017 2016 Amortization of Pension and Other Postretirement Benefits Items Amortization of Pension and Other Postretirement Benefits Items Actuarial Losses Recognized Prior Service Costs Recognized Total Actuarial Losses Recognized Prior Service Costs Recognized Total Affected Line in Consolidated Statement of Income: Selling, general and administrative expenses $ 22,291 $ (1,761 ) $ 20,530 $ 19,873 $ (1,758 ) $ 18,115 Tax (benefit) expense (8,671 ) 685 (7,986 ) (7,731 ) 684 (7,047 ) Total reclassifications for the period, net of tax $ 13,620 $ (1,076 ) $ 12,544 $ 12,142 $ (1,074 ) $ 11,068
Amounts Recognized in Other Comprehensive Income (Loss)	The following table represents the activity included in accumulated other comprehensive loss for the years ended December 31, 2017 and 2016 : 2017 2016 Foreign Currency Pension and Other Postretirement Benefits Total Foreign Currency Pension and Other Postretirement Benefits Total Beginning balance January 1, $ (10,343 ) $ (186,257 ) $ (196,600 ) $ (12,416 ) $ (178,019 ) $ (190,435 ) Other comprehensive income before reclassifications 5,741 — 5,741 2,073 — 2,073 Amounts reclassified from accumulated other comprehensive loss (net of tax $(7,986) and $(7,047)) — 12,544 12,544 — 11,068 11,068 Actuarial loss, (net of tax $18,033 and $12,292) — (28,324 ) (28,324 ) — (19,306 ) (19,306 ) Net current-period other comprehensive income (loss) 5,741 (15,780 ) (10,039 ) 2,073 (8,238 ) (6,165 ) Adoption of ASU 2018-02 — (43,515 ) (43,515 ) — — — — Ending balance December 31, $ (4,602 ) $ (245,552 ) $ (250,154 ) $ (10,343 ) $ (186,257 ) $ (196,600 )

Quarterly Financial Informati36

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information (Unaudited)	The following tables set forth selected quarterly financial data for the years ended December 31, 2017 and 2016 : 2017 For the Quarter Ended March 31, June 30, September 30, December 31, Net sales $ 1,530,571 $ 1,712,880 $ 1,700,843 $ 1,686,933 Gross margin $ 299,829 $ 322,893 $ 321,984 $ 316,601 Net income (loss) attributable to the Company $ 17,681 $ 33,334 $ 29,434 $ (8,841 ) Net income (loss) attributable to the Company per share of common stock (A) $ 0.91 $ 1.72 $ 1.52 $ (0.45 ) (A) All periods adjusted for a 10% stock dividend declared in December 2017 . Prior to these adjustments, the average common shares outstanding for the first, second, third, and fourth quarters of 2017 were 17,620,521 , 17,641,979 , 17,610,573 , and 17,565,590 , respectively. 2016 For the Quarter Ended March 31, June 30, September 30, December 31, Net sales $ 1,465,480 $ 1,630,521 $ 1,689,619 $ 1,599,412 Gross margin $ 279,647 $ 305,599 $ 318,758 $ 304,359 Net income attributable to the Company $ 15,045 $ 25,635 $ 30,129 $ 22,270 Net income attributable to the Company per share of common stock (A) $ 0.79 $ 1.34 $ 1.57 $ 1.17 (A) All periods adjusted for a 10% stock dividend declared in December 2017 and a 5% stock dividend declared in December 2016 . Prior to these adjustments, the average common shares outstanding for the first, second, third, and fourth quarters of 2016 were 16,537,536 , 16,569,408 , 16,573,041 , and 16,558,984 , respectively.

Accounting Policies (Concentrat

Accounting Policies (Concentration Risk) (Details)	12 Months Ended
	Dec. 31, 2017
Sales revenue | Services | Maximum
Concentration Risk [Line Items]
Service revenue, less than	1.00%

Accounting Policies (Details)

Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Outgoing freight expenses	$ 54,545	$ 50,949	$ 51,100
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 1,074

Cash Discounts And Doubtful A39

Cash Discounts And Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reserve for Cash Discount and Allowances for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 5,025	$ 5,879	$ 7,073
Provision (Charged to Expense)	34,708	30,446	28,589
Deductions	(33,744)	(31,300)	(29,783)
Ending Balance	5,989	5,025	5,879
Allowance for cash discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	1,731	1,736	1,764
Provision (Charged to Expense)	31,158	28,174	26,044
Deductions	(30,873)	(28,179)	(26,072)
Ending Balance	2,016	1,731	1,736
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	3,294	4,143	5,309
Provision (Charged to Expense)	3,550	2,272	2,545
Deductions	(2,871)	(3,121)	(3,711)
Ending Balance	$ 3,973	$ 3,294	$ 4,143

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Inventory [Line Items]
Percentage of LIFO Inventory	90.00%	90.00%
Excess of Replacement or Current Costs over Stated LIFO Value	$ 170,885	$ 147,091
Inventory, LIFO Reserve, Effect on Income, Net		131
Inventory Valuation Reserves	9,220	6,553
Inventory Valuation Reserve
Inventory [Line Items]
Reserves for Obsolete Inventories, Period Increase (Decrease)	$ 2,667	$ 1,641	$ 495

Property and Depreciation Sched

Property and Depreciation Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Depreciation	$ 38,824	$ 39,332	$ 38,588
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations [Member]
Property, Plant and Equipment [Line Items]
Net book value of assets held for sale	0	464
Net book value of sold assets held for sale	464	148
Gain on sale of assets held for sale	$ 197	2,004
Building
Property, Plant and Equipment [Line Items]
Estimated useful asset life	42 years
Furniture, Fixtures & Equipment and Software | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful asset life	3 years
Furniture, Fixtures & Equipment and Software | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful asset life	14 years
Software and Software Development Costs
Property, Plant and Equipment [Line Items]
Property plant and equipment additions	$ 4,214	3,542
Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Property plant and equipment additions	1,945	427
Capitalized Interest Costs
Property, Plant and Equipment [Line Items]
Interest costs capitalized	$ 44	$ 0	$ 225

Goodwill and Intangible Asset42

Goodwill and Intangible Assets Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Beginning Balance	$ 30,114	$ 13,737
Goodwill Acquired	0	16,377
Ending Balance	$ 30,114	$ 30,114

Goodwill and Intangible Asset43

Goodwill and Intangible Assets Schedule of Finite Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 31,869	$ 31,869
Accumulated Amortization	(2,169)	(4,760)
Total Net Carrying Amount	29,700	27,109
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	17,163	17,163
Accumulated Amortization	(1,538)	(3,272)
Total Net Carrying Amount	$ 15,625	13,891
Customer Relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	8 years 6 months
Customer Relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	10 years 9 months 18 days
Trade Names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 14,263	14,263
Accumulated Amortization	(543)	(1,292)
Total Net Carrying Amount	$ 13,720	12,971
Trade Names | Minimum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	15 years
Trade Names | Maximum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	20 years
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 281	281
Accumulated Amortization	(84)	(149)
Total Net Carrying Amount	$ 197	132
Noncompete Agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	3 years
Noncompete Agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful lives (in years)	5 years
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 162	162
Accumulated Amortization	(4)	(47)
Total Net Carrying Amount	$ 158	$ 115
Weighted-average useful lives (in years)	10 years

Goodwill and Intangible Asset44

Goodwill and Intangible Assets Finite Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 2,591	$ 1,647
2,018	2,579
2,019	2,547
2,020	2,505
2,021	2,493
2,022	2,493
After 2,022	14,492
Total Net Carrying Amount	$ 27,109	$ 29,700

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
ProvisionalIncomeTaxExpenseRelatedtoTaxCutsandJobsAct	$ 28,840
ProvisionalTaxExpenseRelatedtoDeferredTaxBalances	22,640
ProvisionalTaxExpenseRelatedtoDeferredTaxBalancesPreviouslyRecordedThroughAOCI	43,515
ProvisionalTaxBenefitRelatedtoDeferredTaxBalancesPreviouslyRecordedThroughProvisionforIncomeTaxes	20,875
ProvisionalOneTimeTransitionIncomeTaxExpense	6,200
ProvisionalOneTimeTransitionTaxCurrentLiability	1,174
ProvisionalOneTimeTransitionTaxNonCurrentLiability	5,026
ProvisionalFederalCurrentIncomeTaxExpenseRelatedtoOneTimeTransitionTax	5,067
ProvisionalStateCurrentIncomeTaxExpenseRelatedtoOneTimeTransitionTax	1,133
Unrecognized tax benefits	2,318	$ 1,755	$ 2,247
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1:	1,755	2,247	3,104
Additions based on tax positions related to current year	437	397	464
Additions based on tax positions of prior years	291	0	0
Reductions for tax positions of prior years	(165)	(889)	(252)
Settlements	0	0	(1,069)
Balance at December 31:	2,318	1,755	$ 2,247
Accrued interest and penalties	$ 983	$ 650
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory federal tax rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal benefit	4.00%	3.30%	3.80%
Deemed repatriation of foreign earnings	3.30%	0.00%	0.00%
Effect of tax rate changes	13.50%	0.00%	0.00%
Other, net	1.30%	0.90%	1.20%
Effective tax rate	57.10%	39.20%	40.00%
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Income before Income Taxes, Domestic	$ 155,268	$ 143,567	$ 143,144
Income before Income Taxes, Foreign	12,280	9,932	9,197
Income before Provision for Income Taxes	167,548	153,499	152,341
Provisions for Income Taxes Recorded in the Consolidated Statements of Income [Abstract]
U.S. Federal, current expense	66,475	33,030	46,174
State, current expense	11,396	4,821	7,996
Foreign, current expense	3,574	2,795	2,666
Total current expense	81,445	40,646	56,836
U.S. Federal, deferred expense	15,332	16,676	3,224
State, deferred expense	(1,139)	3,008	958
Foreign, deferred expense	(25)	(144)	(9)
Total deferred (benefit) expense	14,168	19,540	4,173
Total income tax provision	95,613	60,186	$ 61,009
Components of Deferred Tax Assets and Liabilities [Abstract]
Postretirement benefits	19,768	29,788
Payroll accruals	1,866	2,618
Bad debt reserves	1,023	1,322
Other deferred tax assets	4,772	5,251
Pension	37,988	47,847
Inventory	12,123	11,336
Subtotal	77,540	98,162
less: valuation allowances	(23)	(136)
Deferred tax assets	77,517	98,026
Fixed assets	(27,156)	(40,887)
Computer software	(3,240)	(5,724)
Other deferred tax liabilities	(2,622)	(3,043)
Deferred tax liabilities	(33,018)	(49,654)
Net deferred tax assets	44,499	48,372
Deferred Tax Assets, Net, Classification [Abstract]
Deferred tax assets, included in other non-current assets	44,860	48,666
Deferred tax liabilities included in other current liabilities	(361)	(294)
Deferred Tax Assets, Operating Loss Carryforwards, Components [Abstract]
Foreign net operating losses	187	239
State net operating losses	$ 504	$ 529

Capital Stock Par Value of Stoc

Capital Stock Par Value of Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 10, 2004
Class of Stock [Line Items]
Stockholders' Equity Note, Percent of Entity Owned by Current and Retired Employees	100.00%
Common Stock, Shares, Issued, Voting Trustees	15,912,467	14,606,830
Common stock stated value per share (USD per share)	$ 20	$ 20
Common stock, subscriptions ( in shares)	923,156
Common shares subscribed (in dollars)	$ 18,463
Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract]
Shares of common stock purchased	684,347	563,590	718,269
Shares of common stock retired	678,958	610,626	666,861
Preferred stock shares authorized				10,000,000
Preferred stock par or stated value per share (USD per share)				$ 0.01
Preferred stock outstanding (in shares)	0	0
Common stock dividend declared, percent	10.00%	5.00%	2.50%
2017 Voting Trust | Common Stock
Class of Stock [Line Items]
Percentage Ownership in Voting Trust	82.00%

Net Income Per Share of Commo47

Net Income Per Share of Common Stock (Details) - shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Abstract]
Common stock dividend declared, percent									10.00%	5.00%	2.50%
Average shares outstanding	17,565,590	17,610,573	17,641,979	17,620,521	16,558,984	16,573,041	16,569,408	16,537,536	19,367,048	19,124,547	18,900,929

Debt Long-Term Debt (Details)

Debt Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 9,100
Less current portion	(2,052)	$ (4,155)
Long-term Debt	7,048	7,271
Long-term Debt, Fiscal Year Maturity [Abstract]
2,018	2,052
2,019	1,383
2,020	1,213
2,021	1,162
2,022	986
After 2,022	$ 2,304
Capital leases, various maturities, with a weighted average interest rate of 5.97% | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.97%
Capital leases, various maturities, with a weighted average interest rate of 5.97% | Capital Lease Obligations
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 9,100	$ 11,426

Credit Agreement (Details)

Credit Agreement (Details) - USD ($)	Jun. 06, 2014	Dec. 31, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Fixed rate debt carrying amount in excess of fair value		$ 737,000	$ 984,000
Remaining borrowing capacity		$ 380,357,000	$ 409,535,000
Credit agreement commitment fee percentage		0.40%	0.40%
Line of credit | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 550,000,000
Debt Instrument, Term	5 years
Line of credit | Amended Credit Agreement | Minimum | Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Line of credit | Amended Credit Agreement | Maximum | Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.60%
Line of credit | Amended Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Accordion feature, higher borrowing capacity option	$ 300,000,000
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Base Rate
Line of Credit Facility [Line Items]
Description of variable rate basis	base rate loans
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Eurodollar
Line of Credit Facility [Line Items]
Description of variable rate basis	Eurodollar rate
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Minimum
Line of Credit Facility [Line Items]
Credit agreement commitment fee percentage	0.25%
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Minimum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.00%
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Maximum
Line of Credit Facility [Line Items]
Credit agreement commitment fee percentage	0.40%
Line of credit | Amended Credit Agreement | Revolving Credit Facility | Maximum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.60%
Line of credit | Amended Credit Agreement | Letter of Credit Sub-Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 50,000,000
Line of credit | Amended Credit Agreement | Bridge Loan | Graybar Canada
Line of Credit Facility [Line Items]
Maximum borrowing capacity	100,000,000
Line of credit | Amended Credit Agreement | Bridge Loan | UNITED STATES
Line of Credit Facility [Line Items]
Maximum borrowing capacity	50,000,000
Line of credit | Amended Credit Agreement | Bridge Loan | CANADA
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 20,000,000
Line of credit | Amended Credit Agreement | Letter of Credit | Minimum
Line of Credit Facility [Line Items]
Credit agreement commitment fee percentage	1.00%
Line of credit | Amended Credit Agreement | Letter of Credit | Maximum
Line of Credit Facility [Line Items]
Credit agreement commitment fee percentage	1.60%
Letter of Credit
Line of Credit Facility [Line Items]
Letters of credit outstanding		$ 5,371,000	$ 5,244,000
Letter of Credit | Revolving Credit Facility
Line of Credit Facility [Line Items]
Letters of credit outstanding		$ 0	$ 0

Debt Short-Term Borrowings (Det

Debt Short-Term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Short-term borrowings	$ 169,643	$ 140,465
Short-term debt average amount outstanding	$ 166,000	185,000
Weighted average interest rate	2.60%
Revolving Credit Facility
Line of Credit Facility [Line Items]
Short-term borrowings		$ 140,465
Interest rate during the period	2.16%	1.52%
Minimum
Line of Credit Facility [Line Items]
Short-term borrowings	$ 112,292	$ 105,014
Maximum
Line of Credit Facility [Line Items]
Short-term borrowings	$ 229,782	$ 311,506

Debt Private Placement Shelf Ag

Debt Private Placement Shelf Agreement (Details) - Maximum - Senior Notes - USD ($) $ in Thousands	Sep. 22, 2016	Sep. 22, 2014	Aug. 02, 2017
Prudential Private Placement Shelf Agreement
Debt Instrument [Line Items]
Agreement face amount			$ 100,000
Debt Instrument, Term		12 years
MetLife Private Placement Shelf Agreement
Debt Instrument [Line Items]
Agreement face amount	$ 100,000
Debt Instrument, Term	12 years

Pension and Other Postretirem52

Pension and Other Postretirement Benefits Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Award vesting period	3 years
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 507,287
Balance, end of year	585,380	$ 507,287
Paid from Company assets for unfunded nonqualified benefits	1,589	1,634
Pension Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning of period	669,789	634,068
Service cost	26,415	25,369	$ 25,607
Interest cost	27,818	28,263	25,203
Actuarial loss (gain)	85,618	35,504
Benefits paid from plan assets	(50,136)	(50,422)
Benefits paid from Company assets	(1,589)	(1,634)
Plan participants' contributions	0	0
Administrative expenses paid	(1,603)	(1,359)
Benefit obligation, end of period	756,312	669,789	634,068
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	507,287	447,258
Actual return on plan assets	69,832	31,810
Employer contributions	61,589	81,634
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	0	0
Benefits paid	(51,725)	(52,056)
Administrative expenses paid	(1,603)	(1,359)
Balance, end of year	585,380	507,287	$ 447,258
Unfunded status	170,932	162,502
Accumulated benefit obligation	670,060	592,810
Liability, Defined Benefit Plan [Abstract]
Current accrued benefit cost	1,707	1,552
Non-current accrued benefit cost	169,225	160,950
Net amount recognized	170,932	162,502
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Abstract]
Net actuarial loss	192,456	177,234
Prior service cost (gain)	201	457
Accumulated other comprehensive loss	192,657	$ 177,691
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net actuarial loss	19,965
Prior service cost (gain)	235
Accumulated other comprehensive loss	$ 20,200
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.67%	4.15%
Rate of compensation increase	4.74%	4.52%
Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Net Periodic Benefit Cost	6.00%	6.50%	7.00%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, for Next Fiscal Year, Actuarial Present Value	5.50%	6.50%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate, Actuarial Present Value	5.00%	5.00%
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning of period	$ 76,576	$ 75,937
Service cost	2,327	2,288	$ 2,505
Interest cost	2,844	3,030	2,925
Actuarial loss (gain)	(61)	889
Benefits paid from plan assets	0	0
Benefits paid from Company assets	(6,427)	(6,958)
Plan participants' contributions	1,540	1,390
Administrative expenses paid	0	0
Benefit obligation, end of period	76,799	76,576	75,937
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	4,887	5,568
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	1,540	1,390
Benefits paid	(6,427)	(6,958)
Administrative expenses paid	0	0
Balance, end of year	0	0	$ 0
Unfunded status	76,799	76,576
Liability, Defined Benefit Plan [Abstract]
Current accrued benefit cost	6,052	5,948
Non-current accrued benefit cost	70,747	70,628
Net amount recognized	76,799	76,576
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Abstract]
Net actuarial loss	10,575	11,093
Prior service cost (gain)	(1,195)	(2,527)
Accumulated other comprehensive loss	9,380	$ 8,566
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net actuarial loss	613
Prior service cost (gain)	(1,453)
Accumulated other comprehensive loss	$ (840)
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.44%	3.78%
Rate of compensation increase	0.00%	0.00%
Defined Benefit Plan Ultimate Health Care Cost Trend Rate For Benefit Obligation, Net Periodic Benefit Cost	5.00%	5.00%	5.00%

Pension and Other Postretirem53

Pension and Other Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 351,483	$ 172,521
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Estimated nonqualified benefits in next fiscal year	1,626
Estimated future employer contributions in next fiscal year	$ 40,000
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	100.00%	100.00%
Defined Benefit Plan, Target Allocation Percentage	1	1
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 507,287
Balance, end of year	585,380	$ 507,287
Equity Securities - U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 11,488	$ 9,827
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	8.00%	8.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 40,779
Balance, end of year	46,438	$ 40,779
Equity Securities - International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 0	$ 0
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	10.00%	11.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 55,619
Balance, end of year	59,632	$ 55,619
Fixed Income Investments - U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 296,232	$ 99,383
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	70.00%	62.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 318,095
Balance, end of year	410,679	$ 318,095
Fixed Income Investments - International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 0	$ 0
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	3.00%	5.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 27,346
Balance, end of year	17,210	$ 27,346
Absolute Return
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 24,444	$ 25,479
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	4.00%	5.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 25,479
Balance, end of year	24,444	$ 25,479
Real assets
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 15,565	$ 14,852
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	3.00%	3.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 15,047
Balance, end of year	15,762	$ 15,047
Private equity
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 0	$ 0
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	1.00%	1.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 1,942
Balance, end of year	7,461	$ 1,942
Short-term Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan fair value of plan assets measured at net asset value	$ 3,754	$ 22,980
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Actual Allocation	1.00%	5.00%
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	$ 22,980
Balance, end of year	3,754	$ 22,980
Quoted Prices in Active Markets for Identical Inputs (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	332,629
Balance, end of year	226,239	332,629
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Equity Securities - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	30,952
Balance, end of year	34,950	30,952
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Equity Securities - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	55,619
Balance, end of year	59,632	55,619
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Fixed Income Investments - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	218,712
Balance, end of year	114,447	218,712
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Fixed Income Investments - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	27,346
Balance, end of year	17,210	27,346
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Absolute Return
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Real assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Private equity
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) | Short-term Investments
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Equity Securities - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Equity Securities - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Fixed Income Investments - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Fixed Income Investments - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Absolute Return
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Real assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Private equity
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Other Observable Inputs (Level 2) | Short-term Investments
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	2,137
Balance, end of year	7,658	2,137
Significant Unobservable Inputs (Level 3) | Equity Securities - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3) | Equity Securities - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3) | Fixed Income Investments - U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3) | Fixed Income Investments - International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3) | Absolute Return
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Significant Unobservable Inputs (Level 3) | Real assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	195
Balance, end of year	197	195
Significant Unobservable Inputs (Level 3) | Private equity
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	1,942
Balance, end of year	7,461	1,942
Significant Unobservable Inputs (Level 3) | Short-term Investments
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0
Balance, end of year	0	0
Pension Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	26,415	25,369	$ 25,607
Interest cost	27,818	28,263	25,203
Expected return on plan assets	(30,631)	(27,016)	(28,297)
Net actuarial loss	21,503	19,164	20,028
Prior service cost (gain)	420	423	452
Net periodic benefit cost	$ 45,525	$ 46,203	$ 42,993
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.15%	4.48%	4.08%
Expected return on plan assets	5.75%	5.75%	6.25%
Rate of compensation increase	4.52%	4.44%	4.47%
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2,018	$ 48,665
2,019	51,270
2,020	52,701
2,021	51,088
2,022	52,146
After 2,022	276,523
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	507,287	$ 447,258
Realized gains/(losses)	69,832	31,810
Balance, end of year	585,380	507,287	$ 447,258
Pension Benefits | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	2,137	3,160
Realized gains/(losses)	96	193
Unrealized gains/(losses)	(98)	(169)
Purchases	6,891	121
Sales	(1,368)	(1,168)
Balance, end of year	7,658	2,137	3,160
Pension Benefits | Significant Unobservable Inputs (Level 3) | Real assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	195	456
Realized gains/(losses)	0	12
Unrealized gains/(losses)	2	(19)
Purchases	0	0
Sales	0	(254)
Balance, end of year	197	195	456
Pension Benefits | Significant Unobservable Inputs (Level 3) | Private equity
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	1,942	2,704
Realized gains/(losses)	96	181
Unrealized gains/(losses)	(100)	(150)
Purchases	6,891	121
Sales	(1,368)	(914)
Balance, end of year	7,461	1,942	2,704
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2,327	2,288	2,505
Interest cost	2,844	3,030	2,925
Expected return on plan assets	0	0	0
Net actuarial loss	788	709	1,044
Prior service cost (gain)	(2,181)	(2,181)	(2,181)
Net periodic benefit cost	$ 3,778	$ 3,846	$ 4,293
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	3.78%	4.09%	3.77%
Expected return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	0.00%	0.00%	0.00%
Ultimate health care cost trend rate	5.00%
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2,018	$ 6,156
2,019	6,565
2,020	6,856
2,021	7,026
2,022	7,003
After 2,022	33,742
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	0	$ 0
Realized gains/(losses)	0	0
Balance, end of year	$ 0	$ 0	$ 0
Minimum | Equity Securities - U.S.
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	0.03	.03
Minimum | Equity Securities - International
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.03	.03
Minimum | Fixed Income Investments - U.S.
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.35	.35
Minimum | Fixed Income Investments - International
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.03	.03
Minimum | Absolute Return
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.05	.05
Minimum | Real assets
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.03	.03
Minimum | Private equity
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	0	0
Minimum | Short-term Investments
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.0	0
Maximum | Equity Securities - U.S.
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.15	.15
Maximum | Equity Securities - International
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.15	.15
Maximum | Fixed Income Investments - U.S.
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.75	.75
Maximum | Fixed Income Investments - International
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.10	.10
Maximum | Absolute Return
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.15	.15
Maximum | Real assets
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.10	.10
Maximum | Private equity
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.03	.03
Maximum | Short-term Investments
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Defined Benefit Plan, Target Allocation Percentage	.03	.03

Profit Sharing and Savings Pl54

Profit Sharing and Savings Plan (Details) - Profit Sharing and Savings Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Employer Matching Contribution	$ 907	$ 363
Discretionary Employer Contribution	$ 43,235	$ 41,365	$ 40,020

Commitments and Contingencies55

Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 27,326	$ 25,133	$ 22,685
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,018	25,968
2,019	20,476
2,020	12,985
2,021	8,964
2,022	5,713
After 2,022	$ 10,679

Accumulated Other Comprehensi56

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax	$ (7,986)	$ (7,047)
Accumulated Other Comprehensive Loss	(250,154)	(196,600)	$ (190,435)
Adoption of ASU 2018-02	0
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Adoption of ASU 2018-02	(43,515)	0
Currency translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(4,602)	(10,343)	(12,416)
Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(245,552)	(186,257)	$ (178,019)
Pension Liability | Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	(192,657)	(177,691)
Postretirement Benefits | Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	$ (9,380)	$ (8,566)

Accumulated Other Comprehensi57

Accumulated Other Comprehensive Income (Loss) Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Selling, general and administrative expenses	$ 1,047,157	$ 1,008,729	$ 965,134
Tax (benefit) expense	95,613	60,186	61,009
Total reclassifications for the period, net of tax	(71,935)	(93,313)	$ (91,332)
Reclassification out of AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Selling, general and administrative expenses	20,530	18,115
Tax (benefit) expense	(7,986)	(7,047)
Total reclassifications for the period, net of tax	12,544	11,068
Reclassification out of AOCI | Actuarial Losses Recognized
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Selling, general and administrative expenses	22,291	19,873
Tax (benefit) expense	(8,671)	(7,731)
Total reclassifications for the period, net of tax	13,620	12,142
Reclassification out of AOCI | Prior Service Costs Recognized
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Selling, general and administrative expenses	(1,761)	(1,758)
Tax (benefit) expense	685	684
Total reclassifications for the period, net of tax	$ (1,076)	$ (1,074)

Accumulated Other Comprehensi58

Accumulated Other Comprehensive Income (Loss) Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance January 1,	$ (196,600)	$ (190,435)
Other comprehensive income before reclassifications	5,741	2,073
Amounts reclassified from accumulated other comprehensive loss (net of tax $(7,986) and $(7,047))	12,544	11,068
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax	(7,986)	(7,047)
Actuarial loss, (net of tax $18,033 and $12,292)	(28,324)	(19,306)
Net Unamortized Gain (Loss) Arising During Period, Tax	18,033	12,292
Net current-period other comprehensive (loss) income	(10,039)	(6,165)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	(43,515)	0
Ending Balance December 31,	(250,154)	(196,600)
Foreign Currency
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance January 1,	(10,343)	(12,416)
Other comprehensive income before reclassifications	5,741	2,073
Amounts reclassified from accumulated other comprehensive loss (net of tax $(7,986) and $(7,047))	0	0
Actuarial loss, (net of tax $18,033 and $12,292)	0	0
Net current-period other comprehensive (loss) income	5,741	2,073
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	0	0
Ending Balance December 31,	(4,602)	(10,343)
Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance January 1,	(186,257)	(178,019)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive loss (net of tax $(7,986) and $(7,047))	12,544	11,068
Actuarial loss, (net of tax $18,033 and $12,292)	(28,324)	(19,306)
Net current-period other comprehensive (loss) income	(15,780)	(8,238)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	(43,515)	0
Ending Balance December 31,	$ (245,552)	$ (186,257)

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Acquisition of Business, Net of Cash Acquired	$ 0	$ (59,946)	$ (18,093)
Goodwill	$ 30,114	30,114	13,737
Cape Electrical Supply
Business Acquisition [Line Items]
Acquisition of Business, Net of Cash Acquired		(59,946)
Goodwill		16,377
Other Intangible Assets		$ 23,586
Advantage Industrial Automation
Business Acquisition [Line Items]
Acquisition of Business, Net of Cash Acquired			(18,093)
Goodwill			7,057
Other Intangible Assets			$ 8,283

Quarterly Financial Informati60

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 1,686,933	$ 1,700,843	$ 1,712,880	$ 1,530,571	$ 1,599,412	$ 1,689,619	$ 1,630,521	$ 1,465,480	$ 6,631,227	$ 6,385,032	$ 6,110,299
Gross margin	316,601	321,984	322,893	299,829	304,359	318,758	305,599	279,647	1,261,307	1,208,363	1,154,745
Net income attributable to the Company	$ (8,841)	$ 29,434	$ 33,334	$ 17,681	$ 22,270	$ 30,129	$ 25,635	$ 15,045	$ 71,608	$ 93,079	$ 91,068
Net income attributable to the Company per share of common stock (usd per share)	$ (0.45)	$ 1.52	$ 1.72	$ 0.91	$ 1.17	$ 1.57	$ 1.34	$ 0.79	$ 3.70	$ 4.87	$ 4.82
Common stock dividend declared, percent									10.00%	5.00%	2.50%
Average common shares outstanding by quarter	17,565,590	17,610,573	17,641,979	17,620,521	16,558,984	16,573,041	16,569,408	16,537,536	19,367,048	19,124,547	18,900,929