Changes in Redeemable Noncontrolling Interests (Detail) (JPY ¥) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Beginning balance			¥ 33,902	¥ 28,095
Adjustment of redeemable noncontrolling interests to redemption value			(84)	448
Transaction with noncontrolling interests			934	992
Comprehensive income (loss)
Net income	522	701	1,787	1,601
Other comprehensive income (loss)
Net change of foreign currency translation adjustments			(2,359)	(3,129)
Total other comprehensive income (loss)			(2,359)	(3,129)
Comprehensive income (loss)	989	45	(572)	(1,528)
Cash dividends			(124)	(5,961)
Ending balance	¥ 34,056	¥ 22,046	¥ 34,056	¥ 22,046

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

No definition available.

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- Definition

Foreign Currency Translation Effects Attributable to Redeemable Noncontrolling Interests

+ References

No definition available.

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- Definition

Minority Interest Period Increase Decrease Attributable To Redeemable Noncontrolling Interest

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Redeemable Noncontrolling Interests Dividends Cash

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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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- Definition

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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