Investments In and Loan Receivables from Affiliated Companies (Schedule Of Investments In And Loan Receivables) (Detail) (JPY ¥) In Millions, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Investments in and Advances to Affiliates [Line Items]
Total Investments and loan receivables from affiliated companies	¥ 23,548	¥ 23,890
Affiliated Entity
Investments in and Advances to Affiliates [Line Items]
Loan receivables-current	4,272	5,919
Loan receivables-noncurrent	258	370
Investments	¥ 19,018	¥ 17,601

Current portion of loan receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

No definition available.

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- Definition

Noncurrent portion of loan receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

No definition available.

+ Details

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- Definition

The carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee and total loan receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

No definition available.

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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=16385135&loc=d3e33749-111570

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