Transfer of Financial Assets - Roll-Forwards of Amount of Servicing Assets (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Transfers and Servicing [Abstract]
Beginning balance	¥ 70,254	¥ 63,754
Increase mainly from loans sold with servicing retained	9,546	13,285
Decrease mainly from amortization	(13,959)	(13,518)
Increase (Decrease) from the effects of changes in foreign exchange rates	6,424	6,733
Ending balance	¥ 72,265	¥ 70,254

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122739-111746

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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Balance Type:	debit
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- Definition

Amount of other increase (decrease) to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- References

No definition available.

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