Deferred Tax Assets and Liabilities (Detail) In Millions	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)
Assets:
Net operating loss carryforwards	$ 573	¥ 47,623	¥ 53,841
Allowance for doubtful receivables on direct financing leases and probable loan losses	841	69,917	77,866
Investment in securities	9	726	13,138
Other operating assets	32	2,638	2,339
Accrued expenses	143	11,865	11,815
Other	371	30,981	34,937
Deferred Tax Assets, Gross, Total	1,969	163,750	193,936
Less: valuation allowance	(322)	(26,794)	(42,846)
Deferred Tax Assets, Net, Total	1,647	136,956	151,090
Liabilities:
Investment in direct financing leases	198	16,462	27,109
Investment in operating leases	782	64,992	69,610
Deferred insurance policy acquisition costs	351	29,233	24,407
Policy liabilities	254	21,123	17,910
Undistributed earnings	350	29,111	25,799
Prepaid benefit cost	144	11,992	13,392
Other	403	33,498	50,285
Deferred Tax Liabilities, Total	2,482	206,411	228,512
Net deferred tax liability	$ 835	¥ 69,455	¥ 77,422

Deferred Tax Assets, Investments

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Deferred Tax Assets, Other Operating Assets

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Deferred Tax Liabilities Investment In Operating Leases

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Deferred Tax Liabilities Policy Liabilities

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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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For entities that net deferred tax assets and tax liabilities, represents the unclassified net amount of deferred tax assets and liabilities as of the balance sheet date, which result from applying the applicable enacted tax rate to net temporary differences and carryforwards pertaining to assets or liabilities. A temporary difference is a difference between the tax basis of an asset or liability and its carrying amount in the financial statements prepared in accordance with generally accepted accounting principles that will reverse in ensuing periods.

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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 sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

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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 the estimated future tax deductions arising from currently nondeductible expenses pertaining to increases in liabilities and loss reserves, which can only be deducted for tax purposes when such expenses 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 amount as of the balance sheet date of the estimated future tax effects attributable to policy acquisition costs being expensed for tax purposes but capitalized in conformity with generally accepted accounting principles, which will reverse in future periods when amortization of such capitalized costs cannot be deducted for tax purposes.

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The amount as of the balance sheet date of the estimated future tax effects attributable to differences between the methods used to account for leasing arrangements for tax purposes and under generally accepted accounting principles which will increase future taxable income when such differences reverse.

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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 the difference between the tax basis of pension liabilities funded in advance and the basis of a prepaid pension asset determined in accordance with generally accepted accounting principles. The difference in basis of such costs will increase future taxable income when such basis difference reverses. (Prepaid pension costs represented the cumulative employer's contributions in excess of net pension cost recognized, before the adoption of the recognition provisions of FAS 158. Under FAS 158, prepaid pension costs are no longer recognized in the statement of financial position.)

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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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