Liability for Pension and Other Retirement Benefits (Details 1) (Pension Plans, Defined Benefit [Member]) In Thousands	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)
Plans with accumulated benefit obligations in excess of plan assets:
Accumulated benefit obligations	$ 1,319,952	¥ 109,556,000	¥ 119,363,000
Plan assets	881,578	73,171,000	82,806,000
Plans with projected benefit obligations in excess of plan assets:
Projected benefit obligations	1,521,771	126,307,000	134,348,000
Plan assets	$ 990,819	¥ 82,238,000	¥ 91,255,000

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If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-Subparagraph b

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-Subparagraph b

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-Subparagraph a

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-Subparagraph a

+ Details

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