Investments in and Advances to Affiliated Companies (Details Textual) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)
Investments in and Advances to Affiliated Companies (Textuals) [Abstract]
Owned Investments in affiliated companies accounted for Equity Method Investment Minimum	20.00%	20.00%
Owned Investments in affiliated companies accounted for Equity Method Investment Maximum	50.00%	50.00%
Dividend received from affiliated companies	$ 5,651	¥ 469,000	¥ 329,000	¥ 869,000
Trade notes and accounts receivables from the affiated companies	208,084	17,271,000	17,838,000
Short-term receivables	8,711	723,000	2,222,000
Trade notes and accounts payable	124,807	10,359,000	10,180,000
Net sales Included Sales to Affiliated Companies	514,133	42,673,000	37,058,000	41,821,000
Unappropriate Retained Earnings Included Share of Undistributed Earnings of Affiliated Companies	$ 137,108	¥ 11,380,000	¥ 9,379,000

Equity Method Investment Ownership Percentage Maximum.

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Equity Method Investment Ownership Percentage Minimum.

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Equity method investment short term receivables from affiated companies.

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Equity Method Investment Trade Notes And Accounts Payable To Affiated Companies.

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Equity Method Investment Trade Notes And Accounts Receivables From Affiated Companies.

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Investments in and advances to affiliated companies.

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Sale To Affiliates Included In Net Sales.

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Unappropriate retained earnings included share of undistributed earnings of affiliated companies .

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This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

+ 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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 19

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