Revenues (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue Disaggregation
Revenue	$ 4,681.2	$ 3,418.8	$ 9,167.0	$ 6,257.2
Carbon steel
Revenue Disaggregation
Revenue	2,625.8	2,098.1	5,173.3	3,757.3
Aluminum
Revenue Disaggregation
Revenue	716.8	498.8	1,409.6	961.6
Stainless steel
Revenue Disaggregation
Revenue	807.1	539.5	1,572.0	992.4
Alloy steel
Revenue Disaggregation
Revenue	196.6	134.9	380.3	252.2
Toll processing
Revenue Disaggregation
Revenue	140.2	115.6	275.3	231.2
Other.
Revenue Disaggregation
Revenue	$ 194.7	$ 31.9	$ 356.5	$ 62.5

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
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details