Stock-Based Compensation (Summary of Stock-Based Compensation Plan) (Detail) ¥ / shares in Units, ¥ in Millions	12 Months Ended
Mar. 31, 2020 JPY (¥) ¥ / shares shares
Number of shares
Outstanding at beginning of fiscal year \| shares	4,245,000
Exercised during fiscal year \| shares	2,968,000
Outstanding at end of fiscal year \| shares	1,277,000
Exercisable at end of fiscal year \| shares	0
Weighted-average exercise price
Outstanding at beginning of fiscal year \| ¥ / shares	¥ 1
Exercised during fiscal year \| ¥ / shares	1
Outstanding at end of fiscal year \| ¥ / shares	1
Exercisable at end of fiscal year \| ¥ / shares	¥ 0
Weighted-average remaining contractual term
Outstanding at end of fiscal year	13 years 10 months 28 days
Aggregate intrinsic value
Outstanding at end of fiscal year \| ¥	¥ 157

Share based compensation arrangement by share based payment award options aggregate intrinsic value.

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- Definition

Share based compensation arrangement by share based payment award options weighted average remaining contractual term.

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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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