Consolidated Statements of Cash Flows (Parenthetical) - JPY (¥) ¥ in Millions	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents reported in Cash and cash equivalents	¥ 3,675,554	¥ 3,836,088
Restricted cash and restricted cash equivalents reported in Deposits with stock exchanges and other segregated cash	165	154
Total cash, cash equivalent, restricted cash and restricted cash equivalents	3,675,719	3,836,242
Right-of-use asset	¥ 15,692	¥ 16,317

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3521-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=126999549&loc=SL98516268-108586

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Balance Type:	debit
Period Type:	instant