Goodwill and Intangible Assets (Changes in Goodwill) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Goodwill [Line Items]
Balance at beginning of fiscal year	¥ 95,151	¥ 95,184	¥ 95,176
Impairment losses recognized	(2,155)	0	0
Foreign exchange translation	1	(33)	8
Balance at end of fiscal year	92,997	95,151	95,184
Gross amount of goodwill	169,313	169,489	170,926
Accumulated impairment losses	¥ 76,316	¥ 74,338	¥ 75,742

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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