INVENTORIES (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Inventory Disclosure [Abstract]
Coal stockpiles	$ 543	$ 989
Coal fuel inventories	6,161	3,048
Materials and supplies	34,233	34,954
Reserve for obsolete inventory	(965)	(1,257)
Total	$ 39,972	$ 37,734

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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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before last-in first-out (LIFO) and valuation reserves of ore stockpile material contained on a leach pad, for example, but not limited to, copper or gold ore.

+ References

No definition available.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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Amount of valuation reserve for inventory.

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