Basis Of Presentation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	9 Months Ended
Jul. 02, 2012	Sep. 30, 2012	Apr. 09, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of mining complexes operated		15
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			0.50%
Payments for Repurchase of Redeemable Noncontrolling Interest	$ 17.5

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant