ORIX Corporation Shareholders' Equity (Information about Dividend Payments and Applicable Dividends) (Detail) - JPY (¥) ¥ / shares in Units, ¥ in Millions	6 Months Ended
Sep. 30, 2026	Sep. 30, 2025
O 2025 H1 Dividends
Dividends Payable [Line Items]
Resolution		The board of directors on May 19, 2025
Type of shares		Common stock
Total dividends paid		¥ 65,920
Dividend per share		¥ 57.84
Date of record for dividend		Mar. 31, 2025
Effective date for dividend		Jun. 04, 2025
Dividend resource		Retained earnings
O 2026 H1 Dividends
Dividends Payable [Line Items]
Resolution	The board of directors on May 18, 2026
Type of shares	Common stock
Total dividends paid	¥ 68,675
Dividend per share	¥ 62.34
Date of record for dividend	Mar. 31, 2026
Effective date for dividend	Jun. 03, 2026
Dividend resource	Retained earnings
Effective Date [Member] \| O 2025 H1 Dividends
Dividends Payable [Line Items]
Resolution		The board of directors on November 12, 2025
Type of shares		Common stock
Total dividends paid		¥ 104,883
Dividend per share		¥ 93.76
Date of record for dividend		Sep. 30, 2025
Effective date for dividend		Dec. 09, 2025
Dividend resource		Retained earnings
Effective Date [Member] \| O 2026 H1 Dividends
Dividends Payable [Line Items]
Resolution	The board of directors on November 9, 2026
Type of shares	Common stock
Total dividends paid	¥ 122,593
Dividend per share	¥ 113.56
Date of record for dividend	Sep. 30, 2026
Effective date for dividend	Dec. 07, 2026
Dividend resource	Retained earnings

Resolution of dividends paid.

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Type of shares dividends paid.

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Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480070/505-10-S50-1

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Date the declared dividend will be paid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-3

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-15

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-3

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Describes the declaration as being a special dividend (over and above the normal dividend); as the annual, semi-annual, quarterly dividend, or other normal periodic dividend; or as some other type of dividend.

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