Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax) (Detail) - Fair value hedges - JPY (¥) ¥ in Millions	6 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Foreign exchange contracts \| Life insurance premiums and related investment income
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income	¥ 8,761	¥ 14,454
Foreign exchange contracts \| Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income	(4)	12
Foreign exchange contracts \| Other (income) and expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income	¥ 0	0
Options held/written and other \| Life insurance premiums and related investment income
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income		0
Options held/written and other \| Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income		0
Options held/written and other \| Other (income) and expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in income		¥ 28

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.

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+ Details

ORIX CORP 6-K