Reconciliation of Differences Between Basic and Diluted Earnings Per Share (EPS) (Detail) (JPY ¥) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Income attributable to ORIX Corporation shareholders from continuing operations	¥ 179,499	¥ 112,144	¥ 79,810
Effect of dilutive securities
Expense related to convertible bond	265	1,329	2,364
Income from continuing operations for diluted EPS computation	¥ 179,764	¥ 113,473	¥ 82,174
Weighted-average shares	1,268,081	1,087,883	1,075,095
Effect of dilutive securities
Conversion of convertible bond	40,057	206,635	244,104
Exercise of stock options	2,117	1,546	1,228
Weighted-average shares for diluted EPS computation	1,310,255	1,296,064	1,320,427
Earnings per share for income attributable to ORIX Corporation shareholders from continuing operations:
Basic	¥ 141.55	¥ 103.09	¥ 74.24
Diluted	¥ 137.20	¥ 87.55	¥ 62.23

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Net Income or 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 or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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