Segment Information - Summary of sales by product and service (Details)	12 Months Ended
Dec. 31, 2023 segment item	Dec. 31, 2022 segment item	Dec. 31, 2021 segment item
Segment Information
Number of reportable segments \| item	1	1	1
Number of operating segments \| segment	1	1	1
Sales (as a percent)	100.00%	100.00%	100.00%
Carbon steel
Segment Information
Sales (as a percent)	53.00%	54.00%	58.00%
Stainless steel
Segment Information
Sales (as a percent)	15.00%	17.00%	16.00%
Aluminum
Segment Information
Sales (as a percent)	16.00%	15.00%	14.00%
Alloy
Segment Information
Sales (as a percent)	5.00%	4.00%	4.00%
Toll processing and logistics
Segment Information
Sales (as a percent)	4.00%	3.00%	3.00%
Copper and brass
Segment Information
Sales (as a percent)	2.00%	2.00%	1.00%
Other and eliminations
Segment Information
Sales (as a percent)	5.00%	5.00%	4.00%

Represents the percentage of revenue from sale of goods and services.

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-18

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

+ 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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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Data Type:	na
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- Details

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Namespace Prefix:
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- Details

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