Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2024	Mar. 31, 2023
Assets:
Net operating loss carryforwards	¥ 62,493	¥ 59,516
Allowance for credit losses	8,650	16,382
Investment in securities	14,382	10,515
Accrued expenses	26,401	25,735
Investment in operating leases	12,728	14,999
Property under facility operations	24,996	24,615
Installment loans	5,459	5,445
Unrealized losses on investment in securities	98,025	71,277
Lease liabilities	69,697	79,636
Other	156,516	103,210
Deferred Tax Assets, Gross, Total	479,347	411,330
Less: valuation allowance	(39,046)	(37,287)
Deferred Tax Assets, Net of Valuation Allowance, Total	440,301	374,043
Liabilities:
Net investment in leases	10,867	10,599
Investment in operating leases	175,727	137,618
Unrealized gains on investment in securities	9,139	4,779
Deferred insurance policy acquisition costs	85,830	80,706
Policy liabilities and policy account balances	194,713	150,137
Property under facility operations	22,615	22,022
Other intangible assets	152,125	141,864
Undistributed earnings	95,720	74,935
Prepaid benefit cost	23,473	17,290
Advances paid	8,102	8,346
Right-of-use assets	68,715	78,631
Other	31,946	27,887
Deferred Tax Liabilities, Net, Total	878,972	754,814
Net deferred tax liability	¥ 438,671	¥ 380,771

Deferred Tax Assets, Investments in Operating Leases

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Deferred tax assets, lease liabilities.

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Deferred Tax Assets, Loans

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Deferred tax assets tax assets deferred expenses reserves and accruals allowances for credit losses.

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Deferred tax liabilities advance paid.

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Deferred tax liabilities investment in lease.

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Deferred Tax Liabilities Investment In Operating Leases

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Deferred Tax Liabilities Other Intangible Assets

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Deferred tax liabilities, right-of-use assets.

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Deferred Tax Liabilities Tax Deferred Expense Reserves And Accruals Policy holder Liabilities

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Deferred Tax Liabilities Unrealized Gains Losses On Investment Securities

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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-Topic 740
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount, before allocation of valuation allowances, of deferred tax asset attributable to deductible differences from reserves and accruals, compensation and benefit costs, and other provisions, reserves, and allowances.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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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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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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