Collateralized transactions - Offsetting of the transactions in the consolidated balance sheets (Parenthetical) (Detail) - JPY (¥) ¥ in Billions	Sep. 30, 2023	Mar. 31, 2023
Collateralized Transactions
Gross balance of reverse repurchase agreements which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability	¥ 865	¥ 883
Gross balance of repurchase agreements which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability	3,419	2,394
Gross balance of securities borrowing transactions which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability	1,371	1,449
Gross balance of securities lending transactions which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability	¥ 167	¥ 137

Collateralized transactions

No definition available.

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- Definition

Amount of securities borrowed from entities in exchange for collateral, not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483466/210-20-50-3

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-22

+ Details

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Period Type:	instant

- Definition

Amount of securities loaned to entities in exchange for collateral, not subject to a master netting arrangement.

+ References

+ Details

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- Definition

Amount of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price, not subject to a master netting arrangement.

+ References

+ Details

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- Definition

Amount of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price, not subject to a master netting arrangement.

+ References

+ Details

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