Share Based Compensation Arrangement By Share Based Payment Award Points Grants In Period

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Share Based Compensation Arrangement By Share Based Payment Award Points Outstanding Number

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Share Based Compensation Arrangement By Share Based Payment Award Points Settled In Period

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost capitalized for award under share-based payment arrangement.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Stock-Based Compensation - Additional Information (Detail)		12 Months Ended
	Apr. 01, 2013	Mar. 31, 2020 JPY (¥) Point	Mar. 31, 2019 JPY (¥)	Mar. 31, 2018 JPY (¥)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from the exercise of stock options			¥ 225,000,000	¥ 656,000,000
Unrecognized compensation costs		¥ 0
Points settled for individuals retired \| Point		446,805
Points outstanding \| Point		1,389,603
Stock split implemented	10
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised			25,000,000	118,000,000
Stock-based compensation costs recognized		¥ 0
Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Points granted \| Point		320,250
Stock-based compensation costs recognized		¥ 417,000,000	¥ 413,000,000	¥ 701,000,000