Changes in Redeemable Noncontrolling Interests (Detail) In Millions	12 Months Ended
Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)
Beginning Balance	$ 338	¥ 28,095	¥ 25,396	¥ 24,057
Contribution to subsidiary	122	10,219	0	0
Adjustment of Redeemable Noncontrolling Interests to Redemption Value	0	(73)	(139)	23
Transaction with noncontrolling interests	13	1,063	1,962	1,699
Comprehensive income (loss)
Net Income	35	2,959	2,476	698
Other comprehensive income (loss)
Net change of unrealized gains (losses) on investment in securities	0	0	0	(261)
Net change of foreign currency translation adjustments	(28)	(2,353)	(1,600)	(820)
Total other comprehensive income (loss)	(28)	(2,353)	(1,600)	(1,081)
Comprehensive income (loss)	7	606	876	(383)
Cash dividends	(72)	(6,008)	0	0
Ending Balance	$ 408	¥ 33,902	¥ 28,095	¥ 25,396

Capital Contribution, Subsidiaries

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Comprehensive Income, Net of Tax, Attributable to Redeemable Noncontrolling Interest

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Foreign Currency Translation Effects Attributable to Redeemable Noncontrolling Interests

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Minority Interest Period Increase Decrease Attributable To Redeemable Noncontrolling Interest

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Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Portion Attributable To Redeemable Noncontrolling Interest

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Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Portion Attributable To Redeemable Noncontrolling Interest [Abstract]

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Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax Portion Attributable To Redeemable Noncontrolling Interest

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Redeemable Noncontrolling Interests Dividends Cash

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Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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Amount of net income (loss) for the period allocated to noncontrolling shareholders, partners, or other equity holders in one or more of the entities consolidated into the reporting entity's financial statements other than joint ventures, limited partnerships, operating partnerships or interests held by preferred unit holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(1)

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The carrying value (book value) of an entity's issued and outstanding stock which is not included within permanent equity in Stockholders Equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph i
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number D-98
-Paragraph 2

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 28
-Subparagraph a
-Article 5

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