Financial Risk Management - Hedge accounting items designated as hedging instruments (Detail) - Cash flow hedges [member] - Currency swaps [member] ¥ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2026 USD ($)	Mar. 31, 2026 JPY (¥)
Disclosure of detailed information about hedging instruments [line items]
Notional amount \| $	$ 3,000
Carrying amount – assets of hedging instrument		¥ 64,541
Carrying amount – liabilities of hedging instrument
Line item in the statements of financial position where hedging instruments are included	Other financial assets (Current /Non-current)
Average rate of hedging instrument	144.89	144.89
Receivable Rate Of Hedging Instrument	4.85%	4.85%
Payable Rate Of Hedging Instrument	1.71%	1.71%

Payable Rate Of Hedging Instrument.

No definition available.

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- Definition

Receivable Rate Of Hedging Instrument.

+ References

No definition available.

+ Details

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- Definition

The average price of a hedging instrument. [Refer: Hedging instruments [domain]]

+ References

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

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- Definition

The description of the line item in the statement of financial position that includes the hedging instrument. [Refer: Hedging instruments [domain]]

+ References

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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.

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- Definition

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [domain]]

+ References

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- Definition

The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [domain]]

+ References

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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

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- Details

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- Details

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