Selling, General and Administrative Expenses (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
Component of Operating Other Cost and Expense [Line Items]
Personnel expenses	¥ 31,363	¥ 35,263	¥ 93,032	¥ 98,998
Selling expenses	5,015	4,238	11,929	12,089
Administrative expenses	11,737	13,220	34,809	37,499
Depreciation of office facilities	817	717	2,389	2,113
Total	¥ 48,932	¥ 53,438	¥ 142,159	¥ 150,699

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The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 5

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including share-based compensation, and pension and other postretirement benefit expense.

+ References

No definition available.

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- Definition

Expenses recognized in the period that are directly related to the selling and distribution of products or services.

+ References

No definition available.

+ Details

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 4

-Article 5

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 4

-Paragraph 5A

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