Subsequent Events (Details) (JPY ¥) In Millions, except Per Share data, unless otherwise specified	0 Months Ended
May 11, 2011
Subsequent Events
Dividend per common share	¥ 7
Cash dividend per five common shares	¥ 35
Number of common stock eligible for dividend	5
Cash dividends declared	¥ 8,905

Common stock dividends per American Depositary Share declared.

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- Definition

The number of common stock that is equal to each American Depositary Share.

+ Details

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- Definition

Subsequent Events [Abstract]

+ Details

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- Definition

The aggregate amount of dividends declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

+ Details

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

+ Details

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