Derivative Financial Instruments (Summary of Gains and Losses Information Related to Fair Value Hedges) (Detail) ¥ in Millions	12 Months Ended
Mar. 31, 2018 JPY (¥)
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recorded in income- Derivatives	¥ (23,832)
Gains (losses) recorded in income- Hedged items	19,631
Gains (losses) recorded in income- Net gain (loss) excluded from assessment of effectiveness	(4,201)
Equity-related contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recorded in income- Derivatives	(23,832)
Gains (losses) recorded in income- Hedged items	19,631
Gains (losses) recorded in income- Net gain (loss) excluded from assessment of effectiveness	¥ (4,201)

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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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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Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

+ References

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-Publisher FASB
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