Represents the amount of acquired debt refinanced through proceeds from term loan.

No definition available.

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- Definition

Represents the number of service centers acquired by the entity in a business acquisition.

+ References

No definition available.

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- Definition

Represents the amount of acquisition cost of a business combination allocated to other current and noncurrent liabilities of the acquired entity.

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

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-Publisher FASB

-Name Statement of Financial Accounting Concepts (CON)

-Number 6

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

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- Definition

The amount of acquisition cost of a business combination allocated to the noncurrent portion of the long-term debt assumed from the acquired entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 98-1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph g

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

For an acquired entity, price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 59

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Name Accounting Standards Codification

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-SubTopic 30

-Section 55

-Paragraph 8

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Acquisitions (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			3 Months Ended	12 Months Ended	3 Months Ended			3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 Metals USA	Dec. 31, 2012 Metals USA	Mar. 31, 2013 GH Metal Solutions, Inc	Mar. 31, 2013 Sunbelt Steel Texas, LLC	Dec. 31, 2012 2012 acquisitions	Mar. 31, 2013 Airport Metals (Australia) Pty Ltd	Mar. 31, 2013 Worthington Steel Vonore	Mar. 31, 2013 National Specialty Alloys, LLC	Mar. 31, 2013 McKey Perforated Products Co., Inc.,	Apr. 04, 2013 Subsequent event Unsecured revolving credit facility	Apr. 12, 2013 Subsequent event Senior unsecured notes due 2023	Apr. 12, 2013 Subsequent event Metals USA item	Apr. 12, 2013 Subsequent event Metals USA Unsecured revolving credit facility	Apr. 12, 2013 Subsequent event Metals USA Term loan expiring April 4, 2018	Apr. 12, 2013 Subsequent event Metals USA Senior unsecured notes due 2023
Acquisitions
Price per share (in dollars per share)															$ 20.65
Number of service centers acquired															48
Purchase price															$ 786.0
Acquired debt refinanced through proceeds from debt															466.0
Value of debt assumed															12.3
Maximum borrowing capacity of the credit facility, which used to fund the transaction													1,500.0			1,500.0
Face amount of debt, proceeds from which is used to fund transaction	1,151.9		1,208.9											500.0			500.0	500.0
Transaction costs				3.0
Total assets	5,981.1		5,857.7		1,000.0
Net sales	2,025.3	2,288.3			2,000.0	14.4	10.9		0.7	0.7	20.2	4.8
Total transaction value								226.5							1,250.0
Assumed debt								$ 59.4