ACQUISITION (Details 2) (KA Steel [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
KA Steel [Member]
Business Acquisition [Line Items]
Sales	$ 613.9
Net income	$ 38.6
Net income per common share-basic (in dollars per share)	$ 0.48
Net income per common share-diluted (in dollars per share)	$ 0.48