Condensed Consolidated Statements of Cash Flows (Parenthetical) - JPY (¥) ¥ in Millions	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Mar. 31, 2023
Statement of Cash Flows [Abstract]
Cash and Cash Equivalents	¥ 1,168,945	¥ 1,032,810	¥ 915,107
Restricted Cash	134,675	152,497	139,123
Cash, Cash Equivalents and Restricted Cash	¥ 1,303,620	¥ 1,185,307	¥ 1,054,230	¥ 1,366,908

Amount of cash and cash equivalents restricted as to withdrawal or usage. 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://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
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-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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Name:	us-gaap_RestrictedCashAndCashEquivalents
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant