Reconciliation of the Differences Between Basic and Diluted Earnings Per Share (EPS) (Detail) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)
Earnings Per Share, Diluted [Line Items]
Income attributable to ORIX Corporation from continuing operations	$ 710	¥ 59,063	¥ 28,984	¥ 12,991
Effect of dilutive securities-
Expense related to convertible bond	29	2,393	1,305	392
Income from continuing operations for diluted EPS computation	$ 739	¥ 61,456	¥ 30,289	¥ 13,383
Earnings per share for income attributable to ORIX Corporation from continuing operations:
Basic	$ 6.61	¥ 549.49	¥ 284.43	¥ 146.11
Diluted	$ 5.60	¥ 465.55	¥ 244.96	¥ 140.21
Weighted-average shares	107,489	107,489	101,901	88,910
Effect of dilutive securities-
Conversion of convertible bond	24,412	24,412	21,664	6,472
Exercise of stock options	107	107	86	64
Weighted-average shares for diluted EPS computation	132,008	132,008	123,651	95,446

Earnings per share from continuing operations [Abstract]

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Incremental Common Shares Attributable To Stock Options

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Includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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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.

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This element represents the income or loss from continuing operations attributable to the reporting entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items and cumulative effects of changes in accounting principles, but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any.

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
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The amount of income (loss) from continuing operations per each share of common stock outstanding during the reporting period.

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The amount of income (loss) from continuing operations available to each share of common stock outstanding during the reporting period and each share that would have been outstanding assuming the issuance of common shares for all dilutive potential common shares outstanding during the reporting period.

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Debt securities outstanding shall be assumed to have been converted at the beginning of the period (or at time of issuance, if later), and the resulting common shares shall be included in common shares used to calculate diluted earnings per shares. The dilutive effect of convertible debt securities shall be reflected in diluted Earnings Per Share by application of the if-converted method.

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Net Income (Loss) Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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