Income Taxes (Roll-forward of Interest and Penalties Recognized) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Balance at beginning of fiscal year	¥ 305	¥ 1,260	¥ 2,167
Total interest and penalties in the consolidated statements of income	(52)	(1,770)	(1,218)
Total cash settlements, foreign exchange translation and other	334	815	311
Balance at end of fiscal year	¥ 587	¥ 305	¥ 1,260

The amount of cash settlements and foreign exchange translation and others in estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

No definition available.

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- References

No definition available.

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- Definition

The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-15

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- Definition

The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

+ References

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