Revenue (Tables)

9 Months Ended

Sep. 30, 2018

Revenue from Contract with Customer [Abstract]

Schedule of New Accounting Pronouncements

Condensed Consolidated Balance Sheet

	September 30, 2018
	As Reported		Balance without Adoption		Effect of Change
Merchandise inventory	$	661,530	$	667,907	$	(6,377	)
Other current assets	26,692		26,969		(277		)
Other non-current liabilities	21,288		28,528		(7,240		)
Retained earnings	722,274		721,688		586

Condensed Consolidated Statements of Income

	Three Months Ended  September 30, 2018
	As Reported		Balance without Adoption		Effect of Change
Net sales	$	1,870,251	$	1,871,849	$	(1,598	)
Cost of merchandise sold	1,516,849		1,518,311		(1,462		)

	Nine Months Ended  September 30, 2018
	As Reported		Balance without Adoption		Effect of Change
Net sales	$	5,340,235	$	5,343,529	$	(3,294	)
Cost of merchandise sold	4,324,258		4,327,342		(3,084		)

Disaggregation of Revenue

The following table summarizes the percentages of our net sales attributable to each of our vertical markets for the three and nine months ended September 30, 2018 and 2017:

	Three Months Ended  September 30,				Nine Months Ended   September 30,
	2018		2017		2018		2017
Construction	60.4	%	58.8	%	59.4	%	58.6	%
Industrial & Utility	20.3		21.9		21.4		21.9
CIG	19.3		19.3		19.2		19.5
Total net sales	100.0	%	100.0	%	100.0	%	100.0	%