Inventories (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Coal - NACoal	$ 16.4	$ 13.1
Mining supplies - NACoal	12.8	11.1
Total inventories at weighted average	29.2	24.2
Sourced inventories - HBB	114.0	75.6
Retail inventories - KC	62.2	61.5
Total inventories at FIFO	176.2	137.1
Inventories, net	$ 205.4	$ 161.3

Carrying amount as of the balance sheet date of coal, which is a combustible rock or minerals which are extracted from the ground and used as fuel.

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- Definition

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

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- Definition

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 components used by the entity which are bought from another entity rather than produced by the entity.

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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.

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-Glossary Inventory

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- Definition

Carrying amount as of the balance sheet date of merchandise inventory held by a retailer, wholesaler, or distributor for future sale; includes packaging and other supplies used to store, transport, or present merchandise inventory.

+ References

+ Details

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- Definition

The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods.

+ References

+ Details

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