Investments in and Loan Receivables from Affiliated Companies (Schedule of Financial Information of Affiliated Companies) (Details) (JPY ¥) In Millions	Mar. 31, 2011	Mar. 31, 2010
Current assets	¥ 777,204	¥ 820,828
Total	1,356,852	1,409,033
Current liabilities	435,128	440,238
Noncurrent liabilities	240,363	297,176
Affiliated Entity [Member]
Current assets	54,358	55,958
Noncurrent assets	59,853	62,414
Total	114,211	118,372
Current liabilities	59,068	61,495
Noncurrent liabilities	16,083	19,441
Net assets	¥ 39,060	¥ 37,436

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Concepts (CON)
-Number 6
-Paragraph 25

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 18
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 12
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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The net of assets and liabilities.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer.

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Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.

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Total obligations incurred as part of normal operations that is expected to be repaid beyond the following twelve months or one business cycle.

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