Financial Risk Management - Hedge accounting balance of the cash flow hedge reserve (Detail) ¥ in Millions	12 Months Ended
Mar. 31, 2026 JPY (¥)
Disclosure of detailed information about hedged items [line items]
Amounts of gain (loss) recognized in other comprehensive income	¥ 52,471
Amounts reclassified to profit or loss	(41,450)
Cash flow hedges [member] \| Currency swaps [member]
Disclosure of detailed information about hedged items [line items]
Balance of the cash flow hedge reserve	11,021
Amounts of gain (loss) recognized in other comprehensive income	52,471
Amounts reclassified to profit or loss	¥ (41,450)
Line item in which reclassification adjustment is included	Finance income and finance costs (Interest expense / Other, net)

The description of the line item in the statement of comprehensive income that includes the reclassification adjustments. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods.

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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.

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No definition available.

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The gains (losses) recognised in other comprehensive income on cash flow hedges, net of tax, before reclassification adjustments. [Refer: Cash flow hedges [member]]

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The amount of reclassification adjustments related to cash flow hedges, net of tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Cash flow hedges [member]; Other comprehensive income]

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A component of equity representing the reserve of cash flow hedges in relation to continuing hedges. [Refer: Reserve of cash flow hedges]

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