Inventories (Schedule Of Inventory) (Detail) (JPY ¥) In Millions, unless otherwise specified	Mar. 31, 2012	Mar. 31, 2011
Inventories [Abstract]
Finished products	¥ 119,446	¥ 109,043
Spare parts	25,640	23,960
Work in process	31,495	24,477
Raw materials and supplies	25,489	16,737
Total inventory, net	¥ 202,070	¥ 174,217

Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available 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

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

+ References

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Carrying amount as of the balance sheet date of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Carrying amount as of the balance sheet date of components of assembled products that can be sold directly or indirectly through sales of assembled products.

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