Assets Pledged and Received as Collateral - Additional information (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2023	Mar. 31, 2022
Disclosure of detailed information about financial instruments [abstract]
Loaned securities for which the borrowers have the right to sell or repledge	¥ 14,260,889	¥ 13,243,816
Fair value of securities and bills accepted as collateral	16,259,185	16,777,657
Fair value of securities sold or repledged to others	¥ 10,932,766	¥ 12,023,020

The fair value of collateral held that is permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 15
-Subparagraph a
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-URIDate 2022-03-24

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- Definition

The fair value of collateral sold or repledged that was permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 15
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_15_b&doctype=Standard
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- References

No definition available.

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- Definition

The amount of non-cash collateral assets (such as debt or equity instruments) provided to a transferee, for which the transferee has the right by contract or custom to sell or repledge the collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 9
-IssueDate 2022-03-24
-Paragraph 3.2.23
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=9&code=ifrs-tx-2022-en-r&anchor=para_3.2.23_a&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IAS
-Number 39
-IssueDate 2022-03-24
-Paragraph 37
-Subparagraph a
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-URIDate 2022-03-24

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