Liability for Pension and Other Retirement Benefits (Details 5)	Mar. 31, 2011	Mar. 31, 2010
Domestic plans [Member]
Weighted-average assumptions for benefit obligations
Discount rate	2.00%	2.00%
Assumed rate of increase in future compensation levels (Point-based benefit system)	3.90%	3.80%
Assumed rate of increase in future compensation levels	2.60%	2.60%
Foreign plans [Member]
Weighted-average assumptions for benefit obligations
Discount rate	6.00%	6.00%
Assumed rate of increase in future compensation levels (Point-based benefit system)	0.00%	0.00%
Assumed rate of increase in future compensation levels	4.60%	4.40%

- Definition

Defined benefit plan assumptions used calculating benefit obligation rate of compensation increase point based Benefit system.

+ Details

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j

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