Acquisitions (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Unaudited pro forma information presents consolidated results of operations
Net sales	$ 1,090.6	$ 1,324.9	$ 2,212.2	$ 2,557.0
Net income (loss) attributable to Ryerson Inc.	$ 30.6	$ (4.6)	$ 68.8	$ 0.9

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

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