Income Taxes (Schedule of Components of Deferred Tax Assets and Liabilities) (Details) (JPY ¥) In Millions	Mar. 31, 2011	Mar. 31, 2010
Income Taxes
Allowance for doubtful receivables	¥ 1,465	¥ 1,030
Intercompany profits	7,786	7,483
Adjustment of investment securities	8,273	8,334
Write-downs of inventories and fixed assets	1,708	1,404
Accrued bonus	6,000	5,847
Retirement and pension costs	17,197	19,115
Tax loss and credit carryforwards	3,287	4,025
Other temporary differences	21,661	21,737
Gross deferred tax assets	67,377	68,975
Less: valuation allowance	(986)	(1,509)
Net deferred tax assets	66,391	67,466
Adjustment of investment securities	22,605	25,554
Unremitted earnings of foreign subsidiaries and affiliates	8,237	7,284
Other temporary differences	3,500	3,614
Gross deferred tax liabilities	¥ 34,342	¥ 36,452

The tax effect as of the balance sheet date of the amount of the estimated future tax deductions attributable to income, which arisen from intercompany transactions, recognized only for tax purposes and which will reverse when recognized under generally accepted accounting principles.

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Deferred Tax Assets Unrealized Losses on Available for Sale Securities Gross

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Deferred Tax Assets, Write-down of Inventories and Fixed Assets

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Deferred Tax Liabilities, Adjustment of Investment Securities

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The sum of the tax effects as of the balance sheet date of the amounts of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws ( before the valuation allowance, if any, to reduce such sum amount to net realizable value). Includes any tax benefit realized in deferred tax assets for significant impacts of tax planning strategies.

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The aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; net of deducting the allocated valuation allowance, if any, to reduce such amount to net realizable value.

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The tax effect as of the balance sheet date of the amount of estimated future tax deductions arising from other temporary differences not otherwise specified in the taxonomy.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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The tax effect as of the balance sheet date of the amount of estimated future tax deductions arising from postretirement benefits, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from currently nondeductible expenses in accrued liabilities, which can only be deducted for tax purposes when such items are actually incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from estimated losses reflected in the allowance for doubtful accounts, which can only be deducted for tax purposes when actual bad debts are known, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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The sum of the portions of deferred tax assets as of the balance sheet date for which, based on the weight of available evidence, it is more likely than not will not be realized through future reductions of tax-based income.

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The cumulative amount of all deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A taxable temporary difference is a difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with generally accepted accounting principles that will result in taxable amounts in one or more future periods.

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The cumulative amount of the estimated future tax effects attributable to other temporary differences not otherwise specified in this taxonomy that were expensed for tax purposes but capitalized in conformity with generally accepted accounting principles, or which were recognized as revenue under GAAP but not for tax purposes, which will reverse in future periods.

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The amount as of the balance sheet date of the estimated future tax effects attributable to undistributed earnings of subsidiaries and other recognized entities in countries outside the country of domicile which will increase future taxable income when such earnings are distributed into the country of domicile.

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