Commitments and Contingencies (Narrative) (Details) (JPY ¥) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Amortization expenses under capital leases	¥ 2,269	¥ 4,550	¥ 4,840
Rental expenses under operating leases	4,373	4,942	5,281
Commitments for capital expenditures outstanding	545
Maximum potential amount of undiscounted future payments of financial guarantees	9,178
Payment of surcharge		7,072
Claims for compensation	16,274
Number of asbestos-related lawsuits	10
Number of major asbestos-related lawsuits	6
Number of construction workers represented by lawsuits	416
Number of asbestos-related companies named in a lawsuit is filed	46
Expenses included in selling, general, and administrative expenses	1,155	503	1,155
Accrual of asbestos-related expenses	390	352	721
Additional exposure to loss	¥ 840
Minimum [Member]
Period of guarantee	1
Maximum [Member]
Period of guarantee	10

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Loss Contingency Amount of Claims for Compensation

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Loss Contingency Number of Asbestos Related Lawsuits

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Loss Contingency Number of Defendant Companies in Lawsuits

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Loss Contingency Number of Workers Represented in Lawsuits

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The charge for the use of long-lived depreciable capital leased assets for the period.

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-Name Statement of Financial Accounting Standard (FAS)
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

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Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, before estimated recoveries from reinsurers.

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