Disaggregation of Revenue - Revenue by geographic location (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue
Revenue	$ 3,176,289	$ 3,151,029	$ 9,550,696	$ 9,467,342
United States
Disaggregation of Revenue
Revenue	3,166,822	3,139,811	9,525,620	9,442,107
Canada and Mexico
Disaggregation of Revenue
Revenue	$ 9,467	$ 11,218	$ 25,076	$ 25,235

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details