PENSION PLANS AND RETIREMENT BENEFITS (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Compensation and Retirement Disclosure [Abstract]
Contribution to an individual retirement account as a percentage of employee's eligible compensation under age 45 (in hundredths)	5.00%
Contribution to an individual retirement account as a percentage of employee's eligible compensation age 45 and older (in hundredths)	7.50%
Defined contribution pension plans expense	$ 4.1	$ 3.8
Employer's contribution to defined benefit pension	0.2	0.2
KA Steel Multi-Employer Withdrawal Liability	$ 10.0

Contribution to an individual retirement account as a percentage of employee's eligible compensation age 45 and older.

No definition available.

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- Definition

Contribution to an individual retirement account as a percentage of employee's eligible compensation under age 45.

+ References

No definition available.

+ Details

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- Definition

Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

+ Details

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- Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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