Revenue (Tables)

6 Months Ended

Jun. 30, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of revenue

	For the Three Months Ended   June 30,				For the Six Months Ended   June 30,
	2019		2018		2019		2018
Sales to do-it-yourself customers	$	1,434,146	$	1,372,583	$	2,771,175	$	2,644,997
Sales to professional service provider customers	1,113,485		1,042,390		2,152,266		2,017,399
Other sales and sales adjustments	42,243		41,100		77,041		76,358
Total sales	$	2,589,874	$	2,456,073	$	5,000,482	$	4,738,754