The number of locations under collective bargaining arrangements.

No definition available.

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- Definition

The percentage of employees covered by a collective bargaining agreement as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Percentage of net revenue of the entity's external sales accounted for by the reportable unit.

+ References

No definition available.

+ Details

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- Definition

The number of locations under collective bargaining arrangements that expire within the next twelve months.

+ References

No definition available.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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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

No definition available.

+ Details

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- 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

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Description of the Business and Summary of Significant Accounting Policies (Description of the Business) (Details)	12 Months Ended
	Dec. 31, 2019 segment item	Dec. 31, 2018	Dec. 31, 2017	Mar. 01, 2019
Segment Reporting Information
Workforce represented by collective bargaining agreements (as a percent)	9.00%
Number of Locations Subject to Collective Bargaining Agreements	6
Number of locations subject to collective bargaining agreements that expire	0
Segment Reporting Information
Number of reporting segments \| segment	3
Steel Operations
Segment Reporting Information
Percentage of external net sales	76.00%	75.00%	72.00%
Metals Recycling Operations
Segment Reporting Information
Percentage of external net sales	11.00%	13.00%	15.00%
Steel Fabrication Operations
Segment Reporting Information
Percentage of external net sales	9.00%	8.00%	9.00%
Mining Resources
Segment Reporting Information
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	84.00%
United Steel Supply, LLC
Segment Reporting Information
Acquisition of interest (as a percent)				75.00%