Balance Sheet Related Information (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Inventories
Crude stockpile inventories	$ 60.8	$ 53.4
In-process and finished goods inventories	70.5	65.0
Other raw material, container, and supplies inventories	22.5	25.9
Total	$ 153.8	$ 144.3

Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied for sale.

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

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- Definition

Gross amount of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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Gross amount of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

+ References

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

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