Pension Plans (Summary of Projected Benefit Obligations and Fair Value of Plan Assets for Pension Plans) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2022	Mar. 31, 2021
Japan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	¥ 13,811	¥ 15,104
Fair value of plan assets	0	0
Overseas plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	8,484	123,155
Fair value of plan assets	¥ 6,834	¥ 114,412

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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