Income Taxes (Roll-forward of Unrecognized Tax Benefits) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Operating Loss Carryforwards [Line Items]
Total unrecognized tax benefits at beginning of fiscal year	¥ 12,323	¥ 2,345	¥ 1,867
Gross amount of increases related to positions taken during prior years	199	9,550	224
Gross amount of increases related to positions taken during the current year	328	330	351
Amount of decreases related to settlements	(9,420)	0	0
Foreign exchange translation	(56)	98	(97)
Total unrecognized tax benefits at end of fiscal year	¥ 3,374	¥ 12,323	¥ 2,345

Unrecognized Tax Benefits, Increases Decreases Resulting From Currency Translation

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Amount of increase (decrease) in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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