Commitments and Contingencies (Schedule of Comprised Capital Leased Assets) (Details) (JPY ¥) In Millions	Mar. 31, 2011	Mar. 31, 2010
Commitments and Contingencies
Machinery and equipment	¥ 7,616	¥ 11,633
Accumulated depreciation	(5,839)	(7,572)
Software	237	302
Capital leased assets, total	¥ 2,014	¥ 4,363

Capital Leased Software Assets

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- Definition

Commitments And Contingencies Disclosure [Abstract]

+ Details

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- Definition

The total gross amount of assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 1, 10, 13

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 16
-Subparagraph a(i)

+ Details

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ Details

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- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 13

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 122

+ Details

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