Investment in Affiliates (Detail) In Millions, unless otherwise specified	Mar. 31, 2012 USD ($)	Mar. 31, 2012 JPY (¥)	Mar. 31, 2011 JPY (¥)
Investments in and Advances to Affiliates [Line Items]
Shares	$ 3,604	¥ 296,228	¥ 311,556
Loans	432	35,489	61,820
Investment in affiliates	$ 4,036	¥ 331,717	¥ 373,376

Long-Term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. This does not include advances to clients.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2

-Article 6

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6812-107765

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.2)

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6382870&loc=d3e33749-111570

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

+ Details

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