Commitments and Contingencies (Details) (USD $)	12 Months Ended
Dec. 31, 2012
Company's commitments for agreements with take or pay or other similar commitment provisions
Outstanding construction-related commitments	$ 74,500,000
Number of other steel manufacturing companies also served with a class action antitrust complaint	8
Number of the complaints not brought on behalf of steel product purchasers	1
Commitments with suppliers "take or pay"
Commitment and contingencies
Commodity actual usage period	42 months
Commodity transportation requirements period	8 years
Company's commitments for agreements with take or pay or other similar commitment provisions
2013	106,235,000
2014	10,364,000
2015	2,950,000
2016	1,620,000
2017	1,561,000
Thereafter	3,635,000
Total	$ 126,365,000
Physical commodity requirements utilization period	3 years
Electricity purchase commitment
Company's commitments for agreements with take or pay or other similar commitment provisions
Annual "interruptible service" period at Flat Roll Division	160 hours

Represents the outstanding construction related commitments related to ongoing construction projects.

No definition available.

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- Definition

Represents the number of complaints received that were not brought on behalf of a class consisting of all direct purchasers of steel products.

+ References

No definition available.

+ Details

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- Definition

Number of other steel manufacturing companies which were served with a class action antitrust complaint, filed in the United States District Court.

+ References

No definition available.

+ Details

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- Definition

Maximum annual "interruptible service" period allowed in electricity agreement at one of company's divisions.

+ References

No definition available.

+ Details

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- Definition

Represents the usage period for physical commodity requirements.

+ References

No definition available.

+ Details

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- Definition

Represents the usage period for commodity transportation requirements.

+ References

No definition available.

+ Details

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- Definition

Represents the utilization period for physical commodity requirements.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 7

-Subparagraph b

-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

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the four fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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