Represents the number of days to perform services.

No definition available.

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- Definition

Represents the number of performance obligation from sale of metal products.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of revenue from contract with customer excluding assessed tax from sales of metal products.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	duration

- Definition

Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Balance Type:	debit
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- Details

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- Details

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Revenues (Details) $ in Millions	12 Months Ended
Revenues (Details) $ in Millions	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Revenue Disaggregation
Revenue	$ 11,534.5
Revenue from sales of metal products (as a percent)	94.00%
Number of performance obligations from sales of metal products \| item	1
Shipping and handling costs included in operating expenses	$ 412.7	$ 372.3	$ 346.2
Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		9,721.0	8,613.4
Carbon steel
Revenue Disaggregation
Revenue	6,285.8
Carbon steel \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		5,189.6	4,579.5
Aluminum
Revenue Disaggregation
Revenue	2,210.9
Aluminum \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		1,916.9	1,777.6
Stainless steel
Revenue Disaggregation
Revenue	1,636.1
Stainless steel \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		1,386.3	1,212.5
Alloy
Revenue Disaggregation
Revenue	680.7
Alloy \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		587.8	473.3
Toll processing and logistics
Revenue Disaggregation
Revenue	$ 415.3
Number of days to perform services	1 day
Toll processing and logistics \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		362.1	326.5
Other
Revenue Disaggregation
Revenue	$ 305.7
Other \| Before adoption of ASU 2014-09
Revenue Disaggregation
Revenue		$ 278.3	$ 244.0