Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in amortized cost of financing receivable modified for debtor experiencing financial difficulty.

+ References

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Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Financial Effect of Modifications of Financing Receivable (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Consumer borrowers \| Real estate loans \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction			5.30%
Consumer borrowers \| Real estate loans \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction			0.00%
Consumer borrowers \| Card loans \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction			12.70%
Consumer borrowers \| Card loans \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction			0.70%
Consumer borrowers \| Other \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	16.40%	16.50%	14.60%
Consumer borrowers \| Other \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	11.60%	11.80%	5.30%
Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Japan \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	2.70%
Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Japan \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	2.40%
Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Overseas \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction		7.90%
Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Overseas \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction		6.50%
Corporate borrowers \| Other than non-recourse loans \| Commercial, industrial and other companies \| Overseas \| Maximum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	12.10%	15.20%	8.80%
Corporate borrowers \| Other than non-recourse loans \| Commercial, industrial and other companies \| Overseas \| Minimum
Financing Receivable, Modifications [Line Items]
Interest rate reduction	6.00%	11.80%	6.40%
Term extension \| Consumer borrowers \| Real estate loans
Financing Receivable, Modifications [Line Items]
Term extension			1 year
Term extension \| Consumer borrowers \| Card loans
Financing Receivable, Modifications [Line Items]
Term extension			10 months 24 days
Term extension \| Consumer borrowers \| Other
Financing Receivable, Modifications [Line Items]
Term extension	2 years 6 months	2 years 4 months 24 days	4 years 10 months 24 days
Term extension \| Corporate borrowers \| Non-recourse Loans \| The Americas
Financing Receivable, Modifications [Line Items]
Term extension		2 months 12 days	1 year
Term extension \| Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Japan
Financing Receivable, Modifications [Line Items]
Term extension	6 months	2 years 7 months 6 days	6 months
Term extension \| Corporate borrowers \| Other than non-recourse loans \| Real estate companies \| Overseas
Financing Receivable, Modifications [Line Items]
Term extension		2 years 6 months
Term extension \| Corporate borrowers \| Other than non-recourse loans \| Commercial, industrial and other companies \| Japan
Financing Receivable, Modifications [Line Items]
Term extension	10 months 24 days	10 months 24 days	1 year
Term extension \| Corporate borrowers \| Other than non-recourse loans \| Commercial, industrial and other companies \| Overseas
Financing Receivable, Modifications [Line Items]
Term extension	1 year 7 months 6 days	1 year 1 month 6 days	3 years 1 month 6 days
Term extension \| Loans to Equity Method Investees
Financing Receivable, Modifications [Line Items]
Term extension		6 months	7 months 6 days
Term extension \| Net investment in leases \| Japan
Financing Receivable, Modifications [Line Items]
Term extension	6 months
Principal forgiveness \| Consumer borrowers \| Real estate loans
Financing Receivable, Modifications [Line Items]
Principal forgiveness	¥ 54		¥ 8
Principal forgiveness \| Consumer borrowers \| Card loans
Financing Receivable, Modifications [Line Items]
Principal forgiveness			185
Principal forgiveness \| Consumer borrowers \| Other
Financing Receivable, Modifications [Line Items]
Principal forgiveness			785
Principal forgiveness \| Corporate borrowers \| Other than non-recourse loans \| Commercial, industrial and other companies \| Overseas
Financing Receivable, Modifications [Line Items]
Principal forgiveness	1,405	¥ 11	1,487
Principal forgiveness \| Loans to Equity Method Investees
Financing Receivable, Modifications [Line Items]
Principal forgiveness			624
Principal forgiveness \| Net investment in leases
Financing Receivable, Modifications [Line Items]
Principal forgiveness			¥ 0
Principal forgiveness \| Net investment in leases \| Overseas
Financing Receivable, Modifications [Line Items]
Principal forgiveness	¥ 35