ACQUISITION (Details 2) (KA Steel [Member], USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012
KA Steel [Member]
Business Acquisition [Line Items]
Sales	$ 617.0	$ 1,230.9
Net income	$ 48.3	$ 86.9
Net income per common share-basic (in dollars per share)	$ 0.60	$ 1.08
Net income per common share-diluted (in dollars per share)	$ 0.60	$ 1.08