Subsequent Events (Details2) (Arrium Limited [Member]) In Millions, unless otherwise specified	1 Months Ended
Jul. 31, 2012 tons	Jul. 17, 2012 USD ($)	Jul. 17, 2012 AUD
Subsequent Event [Line Items]
Expected tons per year of product shipped	2,700,000
Expected property and equipment, additions		$ 61.5	60.0

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

Name:	us-gaap_OtherCommitment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant