Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2023	Mar. 31, 2022
Assets:
Net operating loss carryforwards	¥ 59,516	¥ 32,914
Allowance for credit losses	16,382	23,381
Investment in securities	12,745	6,685
Accrued expenses	25,735	23,900
Investment in operating leases	14,999	15,099
Property under facility operations	24,615	27,358
Installment loans	5,445	4,361
Unrealized losses on investment in securities	71,277	29,372
Lease liabilities	79,636	77,367
Other	103,210	91,837
Deferred Tax Assets, Gross, Total	413,560	332,274
Less: valuation allowance	(37,287)	(35,155)
Deferred Tax Assets, Net of Valuation Allowance, Total	376,273	297,119
Liabilities:
Net investment in Leases	10,599	13,501
Investment in operating leases	137,618	121,337
Unrealized gains on investment in securities	4,779	2,505
Deferred insurance policy acquisition costs	74,211	73,077
Policy liabilities and policy account balances	87,150	74,939
Property under facility operations	22,022	21,931
Other intangible assets	141,864	108,257
Undistributed earnings	76,281	59,134
Prepaid benefit cost	17,290	14,483
Advances paid	8,346	8,647
Right-of-use assets	78,631	77,003
Other	28,772	22,081
Deferred Tax Liabilities, Net, Total	687,563	596,895
Net deferred tax liability	¥ 311,290	¥ 299,776

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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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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