Financial Risk Management - Additional Information (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2026	Mar. 31, 2025
Disclosure of nature and extent of risks arising from financial instruments [line items]
Amount accrued for estimated losses	¥ 0
Undiscounted maximum amount of payment for guarantee obligations	158,368	¥ 127,348
Cash flow hedges [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Reserve of cash flow hedges	0
Guarantee of employee loans [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Undiscounted maximum amount of payment for guarantee obligations	¥ 46,848
Consumer finance receivables [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Collateral values in excess for percentage of carrying amounts	80.00%	80.00%
Dealer finance receivable [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Collateral values in excess for percentage of carrying amounts	100.00%	100.00%
Percentage of appreciation of the Japanese yen against the U.S. dollar [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Sensitivity analysis, percentage	1.00%	1.00%
Interest rate risk [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Sensitivity analysis, percentage	1.00%	1.00%

Percentage collateral exceeds carrying value.

No definition available.

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- Definition

The amount of provision for the guarantee of employee loans.

+ References

No definition available.

+ Details

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- Definition

The fluctuation of economic and financial indicators when calculating the impact amount on profit before income taxes.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The amount of the exposure to credit risk on loan commitments and financial guarantee contracts. [Refer: Loan commitments [member]; Financial guarantee contracts [member]; Credit risk [member]]

+ References

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+ Details

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- Definition

A component of equity representing the accumulated portion of gain (loss) on a hedging instrument that is determined to be an effective hedge for cash flow hedges. [Refer: Cash flow hedges [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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